doubt

There is no doubt that exercise is beneficial for maintaining a healthy heart.

(Chinese) 毫无疑问，运动有益于维持心脏健康。

The judge had some doubts about the truth of the witness's story.

(Chinese) 法官对证人所说故事的真实性存有一些怀疑。

I doubt that the train will arrive on time given the heavy snowfall today.

(Chinese) 考虑到今天的降雪量，我怀疑火车能否准时到达。

She began to doubt his promise when he failed to show up for the third time.

(Chinese) 当他第三次没出现时，她开始怀疑他的承诺。