You have my word. I'll come this weekend.

我保证来。我这个周末来。

youdao

You have my word.

我向你保证(是这样)。

youdao

I'll pay you this weekend. You have my word.

这个周末我会还给你的。我保证。

youdao

If you emphasize the word my enough, nobody can do much of anything for me and still have it be my such and such.

每件事都是能这么说的，没有人能为我做任何事，只要这是我的事。

耶鲁公开课 - 死亡课程节选

You have my word.

BBC: Shia LaBeouf drops out of Orphans Broadway debut

You don't have to take me at my word, you can look at my record.

WHITEHOUSE: Remarks by the President at a Campaign Event -- Fairfax, VA

You will have to just take my word on that one.

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