问题

o cause people some health problems, in fact farmore serious _____ than computers do
A:knew
B:had known
C:have known
D:have been knowr
B:had known
C:have known
D:have been knowr
正确答案是:
同类题型
In recent years,more and moreAmericans like traveling during holidays.—_______.
_______ do you have an English party—Once a month.
often the case with children, Amy was better by the time the doctor arrived.
________ pieces of bread do you want—Two, please. And ________ are they
o his research work, the professorcared little about any other things.