问题
选择题
The scientists recommend that studies ________ to find out what side effects the medicine might cause.
A．be done
B．should do
C．will be done
D．are done
答案
答案：A
A [recommend后接宾语从句时，谓语动词用虚拟语气，should可以省略。此题中因为studies是动作的承受者，所以用被动形式。]