It is a little difficult for me to (answer) the question.
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He used to(play) tricks on his classmates.
The author devoted all his time to(write) this book.
—It's too hot. Would you mind_______ the door? —______.Please do it. now.
A. to open, OK
B. opening, Certainly not
C. opening, Of course
D. to open, Good idea
It’s not easy so much homework in one day.
A. for him to do
B. of him to do
C. for him doing
D. of him doing
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