1. had better / had best 表示一种劝告或建议，意思为：最好。had better与 had best意义和用法相同，只不过后者比前者的意思更强烈，因此，一般使用前者。如：

You’d better get some sleep. 你最好去睡一会儿。

We’d better be off. 我们最好走吧。

You’d better apologize to him right now. 你最好马上给她道歉。

You had better put on your coat when you go out. 你出门时，最好穿上大衣。

I have not yet decided as to what papers it had better be sent to. 还没决定最好把它寄给哪些报纸。

2. had better / had best 一般不用于疑问句中，但可用于否定句中，其否定形式为：had better / had best not。如：

I’d better not disturb him. 我最好不要去打搅他。

You’d better not play computer games. 你最好不要玩电子游戏。

You had better not talk with strangers. 你最好不要跟陌生人说话。 

We’d better not go until your sister arrives. 我们最好等你姐姐到了再走。

We had better not bring this up now. 我们最好现在暂不提此事。

Better not wait for him.  最好不要等他。