vouching

He vouched his words by his deeds.

他用自己的明了自己的言辞。

They asked whether I was prepared to vouch for him.

他们问我是否愿意他作担保。

I can vouch for the fact that he is a good worker.

我保他是好员工。

You should give the names of two people who can vouch for your honesty and reliability.

你应该个能担保你诚实可信的人的名字。