____some doubt among scientists about the cause of cancer.
#92930
A
It exists
B
There exists
C
There is existing
D
It is existing
推荐题目
Do you know when ________? 
#93566
A
does the basketball game begin
B
begins the basketball game
C
the basketball game begins
D
will the basketball game begin
______, he can speak three foreign languages fluently.
#92560
A
As he is a baby
B
As is he a baby
C
A baby as he is
D
Baby as he is
_____ in the newspaper that the Japanese Prime Minister will arrive next Monday.
#94133
A
It says
B
It’s said
C
He is said
D
It has said