1. 他們斷定還是呆在原地好。
   They figured it was better to stay where they were.
2. 她斷定那筆錢用得不是地方，而我們在經濟上遇到的困難卻也似乎說明她言之有理。
   She claimed that money had been wasted and our financial difficulties seemed to prove her point.
3. 我確實沒法斷定。
   I really couldn't tell.
4. 從他的外表，我們可以有把握地斷定他煙抽得很兇。
   From his appearance we may safely conclude that he is a chain smoker.
5. 我斷定他有40來歲。
   I judge him to be about 40.

斷的英語翻譯：

定的英語翻譯：