There is no way of knowing why one man makes an important discovery ______ another man, also intelligent, fails.
#30143
A
since
B
if
C
as
D
while
推荐题目
If you want to lead a happy life, you'd better learn to accept life_____it iS.
#31144
A
as
B
that
C
which
D
where
—It’s a long time________I saw you last.—Yes，and what a pity it is now that it will be a long time________we see each other again.
#31909
A
before；since
B
since；when
C
since；before
D
when；before
When we got up this morning, we found the sun rose, ____ it always does, in a clear sky.
#32169
A
what
B
which
C
if
D
as
He has made some spelling mistakes in the paper; ______, they are not serious.
#32609
A
but
B
therefore
C
even if
D
however