_______it took 200 years to move from the steam engine to the Internet, there could be major development in _______ are now considered frontiers(尖端) of science in just the past few ten years.
A. When, which B. While, which
C. While, what D. When, that
Would you drop in at my house this afternoon if _______?
A. you are convenient
B. it is convenient for you
C. it is convenient of you
D. you will be convenient
--- Did you try to _______the manager to come to attend the lecture?
--- Yes. He _______, but he was too busy at that moment.
A. recommend, meant to B.persuade, meant to have
C. suggest, had meant to D. request, was meant
With the situation worsening, the army threatens to_______ if a general election is not to be held as scheduled. So let's _______some serious work.
A. take over, get down to
B. take up, come up with
C. take on, come down with
D. take apart, live up to
Seeing his mother seemed uninterested in the story and _______she remained _______with her cellphone, he chose to massage her back.
A. /, occupied B. that, occupying
C. /, to be occupied D. that, occupied
_______ are playing an important part is well known to us all.
A. That who B. Those who C. Who that D. Who
