为什么说：Where have they been?我知道这是过去完成时,但是为什么不是Where have been they?

为什么说：Where have they been?我知道这是过去完成时,但是为什么不是Where have been they? They have got the walls to where they were before Katrina.请问where引导的地点状语从句前为什么要有to?为什么不能说get the walls where they were? Where have they been? where have they lunch? Where have they been?能不能说：They have been in their room. where have all they flowers where are they为什么要用they where can(could) they have gone to?为什么没有be动词?—— where have they gone?答语急呀 where have they been?是现在完成时吗? I wonder where they have gone这里为什么用have.然后那个gone是过去分词么坐等英语帝! they have no idea at all ()为什么用aa,where he has gone b,where did he goc,which place had he gone d,where has he gone. where are they come from为什么不对?说他们来自那个国家为什么要用where do they come from?where are they come from 为什么不对?do 和 are各在什么情况下用呀? 如何区分定语从句和强调句中的It.that.,说详细一点,Where did they get tu know each other?It was in the park (where) they have a stroll every morning.这题为什么会选where． Where are they going to?这里的to为什么是不用的Where are they going to?答案上说应该是：Where are they going?为什么这里to不用? 1,We have understood where--- 2,They have all read where----《空格怎么填?》 I do not know where they have laid him Where are they going to have a wouderful weekend?