The astronaut did many experiments in the spaceship,            great help for knowing more about space.
#70039
A
which we think it is
B
which we think is of
C
of which we think is
D
we think which is of
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Tomorrow is Sunday. Jim will go hiking with his friends if it ________.
#41360
A
isn’t rain
B
doesn’t rain
C
won’t rain
D
don’t rain
.________they were singing, the teacher came in. 
#72179
A
Before
B
after
C
As
D
Until
Not only       to stay at home , but he was also forbidden to watch TV.
#69804
A
that he was forced
B
he was forced
C
was he forced
D
was forced he