You must play a diamond if you have one.

如果你有方块就必须出。

《牛津词典》

If you have a problem, ask the invigilator.

有问题就问监考人。

《牛津词典》

If you have any comments, just email or SMS.

假如你有任何意见，可发电子邮件或短信。

《牛津词典》

And while you're there, tell us if you have been able to quit smoking, and what advice you might have for others.

VOA: special.2010.05.31

No, no. But if you have a UROP, or you have a sports practice or something, we will allow that.

不行，但是如果你得到本科生研究计划，或者你要进行体育锻炼，我们是能够接受的。

麻省理工公开课 - 固态化学导论课程节选

And I think too, a really good exercise if you wanted to do is, if you have a dictionary,

我也认为，如果你想练习，如果你有字典的话，比较好的练习

有这样的困难 - SpeakingMax英语口语达人

If you have a shorter time horizon, that's not - that's probably not advisable.

NPR: Listeners' Money Questions Answered

But if you have a five-year horizon, you can't count on the next five years being great.

NPR: Listeners' Money Questions Answered

The possibility ought to concern you if you have any Federal Reserve notes in your wallet.

FORBES: Could A Federal Reserve Bank Go Bust?