问题
选择题
－I think students should be allowed _______ homework with friends.
－I disagree. They talk instead of ________ homework.
A．do, doing
B．to do, to do
C．to do, doing
D．doing, to do
答案
答案：C
be allowed to do表示被允许做某事，instead of中的of是介词，表示代替的意思，后跟动词要用doing，故本题选C。