It was not until the beginning of the twentieth century________to explore space.
#93086
A
did man begin
B
when man began
C
that man began
D
then man began
推荐题目
My father made me a promise ___ he would buy me a present if I got a good mark
#93029
A
when
B
which
C
that
D
if
He is not selfish at all; instead he is always _________ to help others in trouble.
#92031
A
possible
B
likely
C
probable
D
willing
It was several years I finally realized David had lied to me.
#94916
A
when;that
B
that;when
C
before;that
D
until;why
It’s time that I my hair cut. It’s the fifth time that I to the barber’s shop.
#92272
A
had; have gone
B
have; have gone
C
have; went
D
had; go