英语周报2020-2021学年上学期高二课标units1~3，book5第七期答案，小编收集了英语周报2020-2021学年上学期高二课标units1~3，book5第七期答案的相关答案，没有答案的敬请期待！完整版的周报答案关注wx号：趣找答案
―What a pity! Their experiment is a failure.―They better under more favourable conditions.A. should have done B. could have doneC. must have done D. may have done 题目和参考答案
20. According to the factory safety rules all accidents be reported to the safety officer.
A. may B. can
C. would D. shall
英语周报2020-2021学年上学期高二课标units1~3，book5第七期答案试题答案
20. D考查情态动词。句意：根据工厂的安全法规，所有的事故都必须向安全官员汇报。shall用于第二、三人称，表示命令、警告、威胁等语气，还可表示依照规定必须做某事。根据rules可知，这里指的是规定。故选D。
