4.The grammar books ___ again and again by bus.A.is read B.are read C.have read D.has read

题目

4.The grammar books ___ again and again by bus.A.is read B.are read C.have read D.has read

答案

B
主语是书,所以应该用被动语态,先排除C和D,books为复数,再排除A