The chairman thought necessary to invite Professor Smith to speak at the meeting .A. that

问题补充：

The chairman thought necessary to invite Professor Smith to speak at the meeting .

A. that

B. it

C. this

D. him

答案：

A. that

(答案→)B. it

C. this

D. him

解析：考查形式宾语。It是形式宾语。真正的宾语是to invite Professor Smith to speak at the meeting .