請問I should have known 點解啊？

should have +past participle或could+have+participle都是一種特別用法；
should have +過去分詞：含有責難或後悔的意思
如：You should have done it earlier（你早就應該做完它才對：但當時沒有早做）
而could + have+過去分詞：是對過去某事的推測或懷疑，
如：He cannot have said so（他不可能這樣說：對他這樣說有所懷疑）
而he should have known就是：他該知道（但事實就是他不知道，是對他有所責難）
希望幫到你！

2007-12-22 22:21:53 補充：
是He cannot have said so（他不可能這樣說：對他有這樣說有所懷疑）

佢個解釋正係好正確呀雖然佢答少咗一個問題.
我想跟你做朋友嘅英文是: I want to make friends with you.
另外,等我再清楚答你這個問題:
have known 為何要加should呢？那麼是知還是不知啊？是否不肯定知不知啊？
最佳答案嗰位朋友已同你講咗話係一種特殊嘅表達法,睇返個中文意思,當然是不知道啦.

I should have known - 我應該一早便知道的，可是當時沒有留意。

"我想跟你做朋友"英文可以是 "Would you like to be my friend?"

I should have known =不知

應該知------->不知
I would like to be a friend with you

2007-12-22 21:26:08 補充：
I would like to be a friend of you

請問I should have known 點解啊？

je 係應該已經知道 ,,係present perfect tense

"我想跟你做朋友"英文點講啊？

i want to make friends with you