在越野障碍赛马比赛中，如果碰到障碍，倒下的会是你，而不是障碍物。

In the steeplechase, if you hit a fence, you went down, not the fence.

《柯林斯英汉双解大词典》

如果碰到麻烦，要赶紧向人求教。

If you get in trouble, don't hesitate to ask for advice.

《新英汉大辞典》

如果碰到塞车来不及赴约，发个短信可能会成为救命稻草。

If you are in a traffic jam, and are late to an appointment, the ability to text can be a lifesaver.

youdao

So if you run into a problem set that just, you don't get, all right? Seek help. Could be psychiatric help, could be a TA. I recommend the TA.

所以如果你碰到了一个,你不懂的问题，好么？求助，可以是精神科，可以是一个助教，我推荐助教。

麻省理工公开课 - 计算机科学及编程导论课程节选

When you have difficulty creating your own work, how do you deal with it?

如果创作碰到障碍了，你如何解决呢？

写作课程比较难 - SpeakingMax英语口语达人

But when you start doing scientific research or financial work, imprecision and rounding errors start to add up.

但如果你碰到涉及科学研究,或财政方面的项目时，不精确度,和错误就会累加。

哈佛公开课 - 计算机科学课程节选