为什么HangZhou is such a beautiful city这个句子中一定要有"a"?"a"可不可以去掉?为什么?

为什么HangZhou is such a beautiful city这个句子中一定要有a?a可不可以去掉?为什么? Hangzhou is such a beautiful city.同义句Hangzhou is____beautiful ___ ___. Hangzhou is ( )beautiful place that ( )many peopel come to visit it every year.A such a ,so B so ,so但是为什么不可以用B? Hangzhou is good place to visit为什么不能用visited where is hangzhou?it is__zhejiang. Hangzhou,is,in,Zhejiang,P Hangzhou is ______ Zhejiang Province. Hangzhou is famous ( )producting silk in China.为什么这个句子介词填for啊 Hangzhou is a good place to visit 为什么要加to i with my parents_____my uncle in Hangzhou是is visiting 还是are visiting?为什么? She is been to hangzhou only t___. hangzhou is in the west of china Hangzhou is famous for its beautiful.S______ Shanghai is to the ___of Hangzhou Hangzhou is f__ for the West Lake. Hangzhou is very f______ for West Lake. hangzhou is famous sa its silk My father is in Hangzhou.He will come back ______(after,in) two days.选什么,为什么