一、We'd是We had 的缩写, had better 加动词原形，表示“建议”，最好做某事。

例句：We'd better go home now.= We had better go home now.我们最好现在回家。

二、We'd是We would的缩写，would like 加动词不定式，意为“想要做某事”。例句：We'd like to have a picnic.=We would like to have a picnic.我们想要去野餐。

三、we'd具体是谁的缩写，要依靠语境判断，联系上下文去判断。