It's my birthday. As if you didn't know!

今天是我的生日。你好像不知道似的！

《牛津词典》

How old would you be if you didn't know how old you are?

如果你现在不知道你自己多大，你觉得你应该是多大？

youdao

If you didn't know them you wouldn't be able to tell that they were girls!

如果你不认识她们，你可能看不出来她们是女孩子！

youdao

Sit down if you want to. I didn't know who I might meet or what they might ask.

VOA: standard.other

And it's like, you wouldn't get these kind of opportunities if you didn't know the right people, you know.

这就是，要是你不认识对了人，你是得不到这些机会的，你知道。

认识更多人 - SpeakingMax英语口语达人

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