Knowledge is the food of thought ________，as long as it is put in our brain，we will grow wiser.
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A
but
B
when
C
then
D
and
推荐题目
___________there are many different types of food, some animals spend their lives eating only one type.
#31689
A
Since
B
Unless
C
Once
D
While
27．In hot weather, an old tyre can break again easily _____it’s mended．
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A
when
B
where
C
which
D
that
There’s no way of knowing why one man makes an important discovery ________ another man, also intelligent, fails.
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A
since
B
if
C
as
D
while
--- I rang you at about ten, but there was no reply. --- Oh, that was probably _____ I was seeing the doctor.
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A
for
B
why
C
when
D
how