问题补充:
Food safety is important. Rules to stop people from food pollution.
A. must make
B. must be made
C. can’t make
D. can’t be made
答案:
A. must make
(答案→)B. must be made
C. can’t make
D. can’t be made
解析:考查含有情态动词的被动语态的基本构成,情态动词+be+过去分词,句意:食品安全是重要的,必须制定规则使人们远离食品污染。Rule和make是被动关系,用must be made,选B。