––– Do you think it's a good idea to make friends with your students?–––________, I do. I think it's a great idea.
. We’ve published large quantities of books This year _______we’ve published three million copies.
. I’ll go to America to strengthen my English _______it isn’t too expensive.
. These achievements_______ without the contribution of Qian Xuesen, a key leader of the New China's nuclear, missile and so on.
. —How about going out for a picnic on Sunday morning? —Hmm.___.The weather is very good these days.
. Greatly frightened by the terrible scene, _______.