We should protect the earth， we will have no water to drink．
#58271
A
so
B
or
C
and
D
but
推荐题目
Many Chinese students think science subjects are ______ foreign languages.
#58582
A
more difficult as
B
less difficult than
C
much difficult than
D
so difficult as
Boys and girls, __________ you choose to wear, your clothes should be clean.
#55826
A
however
B
whatever
C
whenever
D
wherever
Johan didn’t review（复习） the lesson, ___ he couldn’t answer the teacher’s question.
#58129
A
as a result
B
such as
C
because of
D
as well as
–May I go to the concert with you?– I’m afraid not ______you have a ticket, because I have only one.
#56155
A
since
B
if
C
unless
D
though