问题
选择题
---- It is demanded that the letter ___by the end of this week , dad !
----I’ll do it immediately .
A．should mail
B．was mailed
C．mailed
D．be mailed
答案
答案：D
考查虚拟语气。在demand后从句中要求用should +动词原形表示虚拟语气，should可以省略，故选D。