问题补充：
It is requested that each of the teachers invited a performance at the party.
A. give
B. will give
C. has to give
D. must give
答案：
(答案→)A. give
B. will give
C. has to give
D. must give
解析：It is requested that的主语从句中，谓语动词用“should + 动词原形”，should可以被省略，故选A。
