题目

It  is  generally  believed  that  teaching  is________it is a science.       A. an art much as       B. much an art as      C. as an art much as      D. as much an art as 答案：D 解析: 在that 引导的主语从句中含一个as...as引导的比较状语从句。第一个as为副词,  修饰名词前的形容词时,不定冠词放在该形容词之后,名词之前。后一个连词as引导比较状语从句。On Taobao, customers can return goods with no questions asked, but they ______ pay delivery costs.A.have toB.mustn’tC.canD.needn’t