评论
打印
1.Silver is the best conductor of electricity, copper ___ it closely.
A.followed
B.following
C.to follow
D.being followed
2.He asked the worker how long ___ to build the house.
A.it had taken
B.had it taken
C.would it take
D.it was taken
3.In this experimenet, they are wakened several times during the night, and asked to report what they ___.
A.had just been dreaming
B.have just been dreaming
C.are just dreaming
D.had just dreamt
4.That a healthy young man begs on the streets ___ considered a shame.
A.is
B.being
C.are
D.to be
5.Corn originated in the New World and thus was not known in Europe until Columbus found it ___ in Cuba.
A.being cultivated
B.been cultivated
C.having cultivated
D.cultivating
