Expressing "almost" using "chadian mei"
Logically, 差点没 is not that different from 差点. In fact, you shouldn't think of it as a single word; think of the 没 as belonging to what follows 差点 and it makes more sense. Still, it can be a little confusing, and is worth a closer look.
Subj. + 差点 + 没 + Verb Phrase
Note that the "Verb Phrase" part is a desired result. So this structure is literally saying, "almost didn't [Verb Phrase]."
Also note that because you're using 没, you don't use 了 after the verb phrase.
- 我 差点儿 没 想 起来。I did remember it. I almost forgot it.
- 我 差点 没 赶 上 火车。 I almost missed it, but I didn't.I didn't miss the train.
- 他 差点 没 通过 考试。He did pass it. He barely passed the examination.
- 排队 的 人 太 多 了，差点儿 没 买到。I did get it.The waiting line is too long. I almost didn't get it.