为什么不可以说as a clever student as,而可以说是as clever a student as

she is as clever a student as us还是she is as a clever student clever a boy as he As students=As a student吗? John is _____ his brother.A.as clever as B.so clever as C.cl As a student, you must study hard. as a student, he strikes me as being a clever man.为什么as后面要加一个being可以省略bein as far as a qualified modern student is concerned he as well as I is a student还是students? as a high school student… what should do as a student my life as a junior three student She is clever as well as beautiful.