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10 tháng 10 2017

I.

There is a considerable public concern in Shaston following the (1.discover) DISCOVERY on Wednesday evening of a metal (2.contain) CONTAINER filled with (3.poison) POISONED liquid. The object was found by a local (4.reside) RESIDENT when he was walking with his lovely dog in a field behind a newly built chemical factory. As yet the factory has been (5.able) UNABLE to provide any (6.explain) EXPLAINATION as to show how the object came to be in the field. A spokesperson stated that a full inverstigation was taking place and that security procedures were being reviewed.

People living in the (7.neighbor) NEIGHBORHOOD are (8.extreme) EXTREMELY angry, as a year ago they withdrew their objections to the (9.decide) DECIDER to build the factory here after the company had stated that no dangerous (10.chemistry) CHEMICAL would be produced on this site

10 tháng 10 2017

Explaination=>Explanation mới đúng nhé bạn

II. Complete the paragraph by using the correct form of thw words in brackets. ------------------------ A STRANGE OBJECT IN THE FIELD ------------------------ There is a considerable public concern in Shaston following the (21. discover) ............ on Wednesday evening of a metal (22. contain) ................... filled with (23. poison) liquid. The object was found by a local (24. reside) ............ when he was walking with his lovely dog in the field behind a newly, built chemical...
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II. Complete the paragraph by using the correct form of thw words in brackets.

------------------------ A STRANGE OBJECT IN THE FIELD ------------------------

There is a considerable public concern in Shaston following the (21. discover) ............ on Wednesday evening of a metal (22. contain) ................... filled with (23. poison) liquid. The object was found by a local (24. reside) ............ when he was walking with his lovely dog in the field behind a newly, built chemical factory. As yet, the factory has been (25. able) .......... to provide any (26. explain) .................. as to show how the object came to be in the field. A spokesperson stated that a null investigation was taking place and that security procedures were being reviewed.

People living in the (27. neighbour).............. are (28. extreme) ................. angry, as a year ago they withdrew their objections to the (29. decide) ............... to build the factory here after the company had stated that no dangerous (30. chemistry) ................... would be produced on this site

3
23 tháng 9 2018

There is a considerable public concern in Shaston following the (21. discover) ....discovery... on Wednesday evening of a metal (22. contain) .....container..... filled with (23. poison)poisoned liquid. The object was found by a local (24. reside) ....resident... when he was walking with his lovely dog in the field behind a newly, built chemical factory. As yet, the factory has been (25. able) ...unable... to provide any (26. explain) ....explanation... as to show how the object came to be in the field. A spokesperson stated that a null investigation was taking place and that security procedures were being reviewed.

People living in the (27. neighbour).....neighborhood... are (28. extreme) ........extremely.... angry, as a year ago they withdrew their objections to the (29. decide) ....decision..... to build the factory here after the company had stated that no dangerous (30. chemistry) .......chemical..... would be produced on this site

23 tháng 9 2018

There is a considerable public concern in Shaston following the (21-discover) ____discovery_____ on Wednesday evening of a metal (22-contain) ____container_____ filled with (23-poison) ____poisoned_____ liquid. The object was found by a local (24-reside) ____reisidence_____ when he was walking with his lovely dog in a field behind a newly- built chemical factory. As yet, the factory has been (25-able) ____unable_____ to provide any (26- explain) ____explaination_____ as to show how the object came to be in the field. A spokesperson stated that a full investigation was taking place and that security procedures were being reviewed.
People living in the (27-neighbor) ____neighborhood_____ are (28-extreme) ____extremely_____ angry, as a year ago they withdrew their objections to the (29- decide) ____decider_____ to build the factory here after the company had stated that no dangerous (30-chemistry) ____chemical_____ would be produced on this site.

21 tháng 8 2018

There is a considerable public concern in Shaston following the (1.discover) DISCOVERY on Wednesday evening of a metal (2.contain) CONTAINER filled with (3.poison) POISONED liquid. The object was found by a local (4.reside) RESIDENT when he was walking with his lovely dog in a field behind a newly built chemical factory. As yet the factory has been (5.able) UNABLE to provide any (6.explain) EXPLAINATION as to show how the object came to be in the field. A spokesperson stated that a full inverstigation was taking place and that security procedures were being reviewed. People living in the (7.neighbor) NEIGHBORHOOD are (8.extreme) EXTREMELY angry, as a year ago they withdrew their objections to the (9.decide) DECIDER to build the factory here after the company had stated that no dangerous (10.chemistry) CHEMICAL would be produced on this site

21 tháng 8 2018

bạn giỏi vậy

II. Supply the correct form of the word in each bracket to complete the passage. ​There is a (1- consider)…..................……public concern in Shaton following the (2- discover).........................on Wednesday evening of a metal (3- contain)……..........…filled with (4- poison)................…….liquid. The object was found by a local ( 5- reside)….................….when he was walking with his lovely dog in a field behind a newly- built chemical factory. As yet, the factory has been...
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II. Supply the correct form of the word in each bracket to complete the passage.

 ​There is a (1- consider)…..................……public concern in Shaton following the (2- discover).........................on Wednesday evening of a metal (3- contain)……..........…filled with (4- poison)................…….liquid. The object was found by a local ( 5- reside)….................….when he was walking with his lovely dog in a field behind a newly- built chemical factory. As yet, the factory has been (6- able)…............................…to provide any (7- explain)…......…..as to how the object came to be in the field. A spokesperson stated that a full (8- investigate)….......................was taking place and that (9- secure)….................……procedures were being reviewed . People living in the (10- neighbor)…...................….are very angry, as a year ago they withdrew their objections to the (11- decide)...............................…to build the factory here after the company had stated that no (12- danger)……............chemicals would be produced on this site. 

Answer:

1.

7.

2.

8.

3.

9.

4.

10.

5.

11.

6.

12.

1. He is completely (employ) …………..! Not only is he lazy but he is dishonest aawell.

2. Visitors complained about the (organize) ……….. in the old museum.

3. Even if you are good at a game, you shouldn’t be (confidence) …………..

4. The old fishing village is very (picture) ………………..

5. (flexible) ………. is one of the qualities required of a social worker.

6. He was arrested for (hand) ……….. stolen goods.

7. She is training to become a (beauty) …………..

8. He can’t afford to buy a house, so he is looking for an (expensive) ……… flat.

1
29 tháng 8 2021

There is a considerable public concern in Shaston following the DISCOVERY on Wednesday evening of a metal (2.contain) CONTAINER filled with (3.poison) POISONED liquid. The object was found by a local (4.reside) RESIDENT when he was walking with his lovely dog in a field behind a newly built chemical factory. As yet the factory has been (5.able) UNABLE to provide any (6.explain) EXPLAINATION as to show how the object came to be in the field. A spokesperson stated that a full inverstigation was taking place and that security procedures were being reviewed. People living in the (7.neighbor) NEIGHBORHOOD are  extremely angry, as a year ago they withdrew their objections to the (9.decide) DECIDER to build the factory here after the company had stated that no dangerous chemical would be produced on this site

1 unemployed

2 organization

3 unconfident

4 pictureque

5 Flexibility

6 handing

7 Beautician

8 inexpensive 

I/ Match A and B A B 1. You have a hiccup 2. He touched a hot burner on the stove 3.He walked barefoot on some glass 4.You shouldn't eat too much so quickly 5. He had a toothache 6.She sneezed 7. It was so smoky 8. He missed a step walking downstairs a. He burned his finger b. Because of the dust in the room c. You may have a stomachache d. That he could not stop coughing e.Take a drink of water f. He...
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I/ Match A and B

A B

1. You have a hiccup

2. He touched a hot burner on the stove

3.He walked barefoot on some glass

4.You shouldn't eat too much so quickly

5. He had a toothache

6.She sneezed

7. It was so smoky

8. He missed a step walking downstairs

a. He burned his finger

b. Because of the dust in the room

c. You may have a stomachache

d. That he could not stop coughing

e.Take a drink of water

f. He went to the dentist

g. He cut his foot

h.He twisted his ankle

1........... 2........... 3............ 4............. 5............

6........... 7............. 8.............

II/ Fill in the blank with a suitable word

1. It was quite a bad cut and it was bleeding a lot, so I put on a ...........

2. He was ten kilos overweight and was advised to go on a ..............

3. You've eaten too much; that's why you have a pain in your .............

4. If you want to stay fit, don't eat too much and take plenty of ............ every day.

5. He .......... out at the gym to keep fit.

6. I have to go to the............ .I've got two fillings done.

7. I went to the doctor and she prescribed some ............

8. He coughs and sneezes a lot. I think he has a .............

III/ Fill in the gap with the suitable word. The intitial letter has been given for you

1. If you want a visa, you must book a r.......... ticket.

2. He has the flu so he has to stay at home on s........... leave.

3. When someone is leaving, you can say to them "Have a nice j.........."

4. A c............ is a trip on the sea visiting different places.

5. I'd love to move to the country and live in a old c.............

6. In the city centre, inexpensive a.......... is hard to find because it is scarce.

7. The main symptom of a cold is that you keep s...........

8. She was in terrible pain and the nurse gave her an i...........

9. He has worked so much on the computer today so he has a terrible

h...........

10. When I'm on holiday, I enjoy s......... on the beach.

IV/ Read the following paragraph and write the correct word (printed in bold type) for each definition.

The world's oceans are so vast that they can cope with the present levels of pollution. However, little is known about the long term effects of such slow poisoning. The most serious problem of modern times is that man is destroying the earth's natural resources and transforming huge areas into wasteland. As a result, it is becoming extremely difficult to grow enough to feed the world's rapidly increasing population. A way of protecting all the wildlife on the earth must also be found as many species are in danger of disappearing completely from the face of the earth. The dangers, however, are not confined solely to the land and the sea. The smoke in the atmosphere, for example, in increasing so much that the amount of sunlight has been reduced in many cities. Man's whole environment is being changed in a serious way.

1. birds, animals, fish which are not tame ...........................

2. keeping something safe from harm ...........................

3. The process of making something dirty ................

4. barren area, desert ......................

5. the air, water and land in which we live.....................

6. causing damage ......................

7. wealth, goods or products people can use ...................

8. The air surrounding the earth .....................

9. the number of people living in one place .......................

10. results, consequences .............................

V/ Complete the paragraph by using the correct form of the words in brackets.

A STRANGE OBJECT IN THE FIELD

There is a considerable public concern in Shaston following the (discover).............. on Wednesday evening of a metal (contain)............... filled with (poison).............. liquid. The object was found by a local (reside).............. when he was walking with his lovely dog in a field behind a newly built chemical factory. As yet, the factory has been (able)........... to provide any (explain)............. as to show how the object came to be in the field. A spokersperson stated that a full investigation was taking place and that security procedures were being reviewed.

People living in the (neighbor)............are extremely angry, as a year ago they withdrew their objection to the (decide).............. to biuld the factory here after the company had stated that no dangerous (chemistry).............. would be produced on this site.

1
10 tháng 2 2019

V/ Complete the paragraph by using the correct form of the words in brackets.

A STRANGE OBJECT IN THE FIELD

There is a considerable public concern in Shaston following the (discover)...discovery........... on Wednesday evening of a metal (contain)....container........... filled with (poison)....poisonous .......... liquid. The object was found by a local (reside).....resident......... when he was walking with his lovely dog in a field behind a newly built chemical factory. As yet, the factory has been (able)....unable....... to provide any (explain)...explanation.......... as to show how the object came to be in the field. A spokersperson stated that a full investigation was taking place and that security procedures were being reviewed.

People living in the (neighbor)..neighborhood..........are extremely angry, as a year ago they withdrew their objection to the (decide)....decider.......... to biuld the factory here after the company had stated that no dangerous (chemistry)...chemical........... would be produced on this site.

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

Which of the following is TRUE about the function of the glass in the first flashbulbs? 

A. It produced the spark that initiated the flash. 

B. It magnified the light produced by the flash. 

C. It protected the photographer from the heat of the flash. 

D. It kept the metal and oxygen apart before the flash.

1
30 tháng 7 2017

Đáp án D

Điều nào dưới đây là ĐÚNG về chức năng thủy tinh trong chiếc bóng đèn flash đầu tiên được sử dụng?

A. Nó tạo ra tia lửa để khởi động đèn flash

B. Nó phóng đại ánh sáng do đèn flash tạo ra

C. Nó bảo vệ các nhiếp ảnh gia khỏi sức nóng của đèn flash

D. Nó giữ cho kim loại và oxy tách rời nhau trước khi đèn nháy

Dựa vào thông tin trong đoạn 2:

"In the earliest type, the metal was separated from the oxygen by a thin glass bulb” (Ở loại bóng đèn lần đầu được sử dụng, kim loại được tách rời khỏi oxy bằng một bóng đèn thủy tinh mỏng.)

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

Which of the following most accurately reflects the main idea of the last paragraph? 

A. The time when photoflash was first used. 

B. How metal burns in an atmosphere of pure oxygen. 

C. How early photoflash worked. 

D. The role of glass in flashbulb.

1
21 tháng 8 2017

Đáp án C

Câu nào dưới đây phản ảnh chính xác nhất ý chính của đoạn cuối?

A. Đèn flash lần đầu tiên được sử dụng là khi nào.

B. Làm sao kim loại cháy được trong môi trường oxy tinh khiết.

C. Cách thức hoạt động của đèn flash đời đầu.

D. Vai trò của thủy tinh trong bóng đèn flash.

Căn cứ vào thông tin trong đoạn cuối: đã được trích dẫn trong các câu 38, 39, và 40, ta dễ dàng nhận thấy đoạn này nói về cách tạo ra tia flash ở loại đèn flash đời đầu tiên.

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

The word "momentarily"  in paragraph 2 is closet in meaning to ______. 

A. effortlessly

B. briefly 

C. electronically 

D. gradually

1
24 tháng 1 2018

Đáp án B

Từ “momentarily” trong đoạn 2 gần nghĩa với từ ___________.

A. effortlessly /'efətlisli/ (adv): một cách dễ dàng

B. briefly /'bri:fli/ (adv): một cách ngắn gọn

C. electronically /ilek'trɔnikli/ (adv): bằng điện tử

D. gradually /'grædjuəli/ (adv): dần dần, từ từ

Căn cứ vào ngữ cảnh đoạn 2:

“In each case, enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of Visible light.” (Trong mỗi trường hợp, một năng lượng vừa đủ được cung cấp để đốt cháy kim loại có thể oxy hóa trong giây lát để phát ra ánh sáng nóng trắng mà mắt thường có thể thấy được.)

=> Do đó, đáp án là B

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

 The word "ignited" in paragraph 1 is closest in meaning to ______.

A. set on fire

B. cut into 

C. opened 

D. shaken

1
1 tháng 8 2019

Đáp án A

Từ "ignited” trong đoạn 1 gần nghĩa nhất với __________.

A. đốt cháy          B. cắt                     C. mở                            D. rung

Căn cứ vào thông tin đoạn 1:

Tạm dịch: “When the bag was ignited, the metal burned with an intense flash." (Khi chiếc túi được đánh lửa, kim loại bị đốt cháy với ánh sáng dữ dội.)

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

The word "it" in paragraph 2 refers to _____. 

A. oxygen

B. battery 

C. wire 

D. current

1
23 tháng 11 2019

Đáp án C

Từ "it” trong đoạn 2 đề cập đến

A. khí Oxy           B. Pin                    C. dây dẫn                    D. dòng điện

Căn cứ vào thông tin đoạn 2:

“The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it.” (Đèn flash được đốt sáng bằng cách xuyên thủng bóng đèn và cho phép oxy tiếp xúc với kim loại, khiến nó tự bốc cháy. Sau đó, những bóng đèn thắp sáng bởi một pin điện, pin này làm nóng dây dẫn bằng cách truyền một dòng điện nhỏ qua nó - tức là dây dẫn.)

Các đáp án còn lại có xuất hiện trong bài nhưng không chính xác nên ta

=> Do đó, đáp án là C