就这样讲英语。。。。。(3)

初学英语者对过去式(PAST TENSE)有高度的知觉性，一看到COULD 或 HAD 就认定是过去式(PAST TENSE)，这可能会带来不同的解意。

Can 的过去式(PAST TENSE)是 Could，但，如用在问题上可以视为较客气的要求，请求的用意。

Can we go home now?

Could we go home now?

Can I take this?

Could I take this?

以上两个都可以，但could 是比较客套！

Had 是 has 和have 的过去式(PAST TENSE)，但如果had 的后面是 better， 你就不可把 had better 这两个字当为过去式(PAST TENSE)的语法了！

Had better 是用来劝告，督促听者的运作，不可当着过去式来用；所以一切在had better后面的动词是不可换着，保持原态（infinitive）。如下

You had better go home now. It is late now.

I had better take a day off I am quite tired.

也有人把had 扔掉 只用better。如

The weather is too hot. You better drink a lot of water.

You better come tomorrow. All of us are waiting you.