The expert offered us another piece of advice,_____of great help to our program. 
#73723
A
I think it is
B
I think which is
C
which I think it is
D
which I think is 
推荐题目
We felt amazed at the use  the waste bottles.
#71625
A
they had made
B
they had made of
C
they had put
D
they had put to
Tom  is _______John .    
#73071
A
so clever a boy as
B
so a clever boy as
C
as a clever boy as
D
as clever a boy as﹡
Owen wouldn't eat anything ________ he cooked it himself.
#67454
A
until
B
since
C
unless
D
while
_______ this sentence a second time, the meaning will become clear to you.
#68068
A
If reading
B
When you read
C
Reading
D
Read