Although the police thought he was the most likely one, _____ they had no exact proof about it, they could not arrest him.
#32949
A
when
B
until
C
before
D
since
推荐题目
Portia，for ________ physics had once been very hard，turned out to be a physicist.
#30489
A
whom
B
whose
C
that
D
which
-----“How long have you stayed in this hotel?”----- “Not long, just ______ this Monday.”
#80015
A
on
B
since
C
until
D
after
_____ computers are convenient to us in daily life, it may also cause other problems.
#33235
A
Whether
B
Because
C
As
D
While
His ability has never been in doubt----the question is ___________ or not he is prepared to work hard.
#31580
A
that
B
if
C
where
D
whether