(2013·高考北京卷)Don’t turn off the computer before closing all programs，________you could have problems.
#30670
A
or
B
and
C
but
D
so
推荐题目
—When did he leave the classroom?—He left _____you turned back to write on the blackboard.
#80113
A
the minute
B
the time
C
until
D
before
_____ computers are convenient to us in daily life, it may also cause other problems.
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A
Whether
B
Because
C
As
D
While
You have failed two tests. You’d better start working harder, ____ you won’t pass the course.
#34819
A
and
B
or
C
but
D
so
I get into the habit of surfing the Internet___I can find a lot of useful information.
#34790
A
which
B
that
C
when
D
where