It seems that he knows everything.为什么要it开头?

it seems that he is ill与it seems that he were ill 的区别? It seems that he has known that He seems to ____ ____ that it seems that he has----- (succeed )solved that problem. It seems that he knows everything.为什么要it开头? It seems that he has had a cold转换He seems　＿　＿　＿acold. 同义句It seems that he is ill He seems ____ ___ill [同义句} ____ he knew nothing about her.A.It seems that B.It seems as if It seems that he is very happy today等于什么 It seems that he is unhappy 同义句He___to___unhappy. It seems that he failed the exam这句话对吗 it seems to us that he knew everything. It seems that he failed the exam这句话对吗? it seems that he is very handsome.同义句 It seems that it seems that 用法 It seems that he knew me.改写成简单句It seems that he knew me.改写成简单句He seems ____ _____ me. It seems that he is quite happy的同义句＿seems __ __quitehappy He seems to have a zoo at home.改写It seems that ______________.