The teacher has a(an) ___________ to get off topic; sometimes it is difficult for students to make out what he is saying.
The reason _____he has just given for not coming to the meeting is______ he missed the bus.. A which; that B. why; that C. . for which; because D. that; why
In the past twenty years great changes _______in China.
The old city wall ______ in the Ming Dynasty.
The doctors have done ______ they could ______the child.
The teacher asked the students ______ .