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
He knows little English that he has never been offered an job.
#93470
A
such;exciting
B
so,exciting
C
so;excited
D
such;excited
When I met him the other day，it was the first time we ____ each other since we graduated from school.
#92015
A
saw
B
have seen
C
were seeing
D
had seen
It is thought that one billion people in the world,_____ is half the world’s workers, earn their living by farming.
#95139
A
if
B
that
C
which
D
what
He is such an unselfish man. You cannot help but ________ him.
#93294
A
respect
B
to respect
C
neglect
D
to neglect