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

It seems that he knows everything.为什么要it开头? It seems that she knows everything.(改为同义句) it seems that she knows everything It's not easy for them to it seems that he has forgotten everything about it seems to us that he knew everything. Lend an ear to him .It seems that he knows the whole story.这 It seems that the policeman knows the truth同义句 it seems that he is right,isn't right?为什么要用right? It seems that he has lost something 同意句转换,it seems that he knows the secret改为同意句___ ___ ___ ___t 帮忙改几个英语同义句1 、It seems that he knows the woman改：____ ____to k it seems that he is ill与it seems that he were ill 的区别?