The scientist, however, goes one step further, he must be sure that he has a reasonableanswer to his questions and that his answer can be confirmed by other persons.

然而，科学家比这更进一步，他必须确定他对自己的问题得出了一个合理的答案，并且他的答案通过别人也可以得到证实。

youdao

She was already sure that he must be Peter, but it did seem a comparatively short name.

她已经知道，他一定是彼得，但相比之下，这个名字似乎有点短。

youdao

Los Angeles physician Bill Kelly echoes the comments of many others, saying he knows that something must be done to avert a financial crisis, but he is not sure the proposed plan is the right one.

洛杉矶一位名叫比尔·凯利的医生的看法就很有代表性。他说，为了防止一场金融危机，必须采取一些行动，但是他并不认为救市计划是正确的。

youdao

When he was sure she was dead, Murlock had sense enough to remember that the dead must be prepared for burial.

VOA: special.2009.10.31

He told Israel Radio that Lebanon must make sure that such incidents will not be repeated.

VOA: standard.2010.08.04

Before acting, he added, the UK must be sure that an offender's country of origin was willing to imprison them for the same length of time as they would serve if they stayed in domestic jails.

BBC: The exterior of Norwich prison

He was sure that there must be a man inside the machine, or a team of brilliant men, whispering killer moves.

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