关系代词是用在定语从句里的,比如I like the book which I bought.里的which；连接代词是用在名词性从句里的,比如I don't believe what is report on TV.里的what.它们本质其实都差不多,都是充当从句里一个名词性成分.前一句定语从句里,which充当的是从句里宾语成分,后一句名词性从句,what充当的是从句的主语成分.
be动词放在哪里?不懂这个问题.