问题补充:
The World War II made impossible for Einstein to go on with his research.
A. him
B. it
C. this
D. that
答案:
A. him
(答案→)B. it
C. this
D. that
解析:考察it作为形式宾语。本句中的it是形式宾语,真正的宾语是后面的to go on with his research。句意:第二次世界大战让爱因斯坦的研究变得不可能。英语中只有it可以作为形式宾语。故B正确。