I'd 是指I could 还是I would?

I'd 是指I could 还是I would? I'd 如何区分是I could还是I would? 怎么区分I’d 是I had 还是I would I’d 是I would fail?还是I had fail? would if i could. i'd rather 的'd是 had还是would I'd bettle hit the books!这句话中的I'd 是I had I would还是 I should? should i would i could i i'd better是i had better还是i would better I'd like you to do me a favor这里i'd 是i would 还是i had 'd 是could 还是would? Would you like to do sth.回答是Yes,I would.还是Yes,I'd like to.还是