Sales of CDs have greatly increased since the early 1990s, when people_____to enjoy the advantages of this new technology.
#104613
A
begin
B
began
C
have begun
D
had begun
推荐题目
When I was in the countryside, I ____ by the riverside every day.
#101180
A
walked
B
was walking
C
walk
D
have walked
The library needs ________, but it’ll have to wait until Sunday.
#104295
A
cleaning
B
be cleaned
C
clean
D
being cleaned
To our great disappointment, a lot of jobs ______ if the factory closes.
#101131
A
will lose
B
will be lost
C
are lost
D
lost
The first few years in the 21st century ______ the rapid rise of China as a world economic power.
#101307
A
witness
B
has witnessed
C
will witness
D
have witnessed
－What a dry day!－We _______ such dry weather for almost twenty days．
#104440
A
have
B
have had
C
have been having
D
have been had