When you can help someone new in town solve a problem, you feel good about it.

VOA: special.2010.07.16

You use "I can't help but" when you feel helpless, when you want to get something across that needs to happen.

当你觉得无助时，或者当你说明需要做到这件事情的时候，你就可以使用“I can't help but”句型。

I can't help but 课堂 - SpeakingMax英语口语达人

Well, you'll know when it crashes, that doesn't help you very much, but you can't always tell whether something's stuck in an infinite loop or whether it's simply taking a long time to compute.

好，你将学到它在什么时候会崩溃，这对你帮助并不大，但是你不能辨别出到底是在一个循环中,有什么东西卡住了呢,还是程序需要很长的时间来计算一个结果呢。

麻省理工公开课 - 计算机科学及编程导论课程节选