14．Mary doesn't have to made . She always works hard. A. learn B. to learn C. learned D. learning 解析:make, let, have等使役动词后面跟动词不定式作宾补时.动词不定式省略to.但如果用被动语态.动词不定式必须加上to. 答案:B 【查看更多】
题目列表(包括答案和解析)
Mary doesn't have to be made ________．She always works hard．
