Listen and read the conversations. Pay attention to the highlighted sentences.
(1) Nick: Do you think Mars may support life?
Mark: I'm not sure about it. Scientists are trying to find life there.
(2) Mary: Do you think Ann will win tomorrow?
Tommy: I doubt it. She injured her arm in a match last week.
I'm not sure about it. (Mình không chắc lắm về nó.)
I doubt it. (Mình phân vân/nghi ngờ chuyện đó.)