Only after spending several nights working on the math problem         to wonder whether the problem was wrongly set.
#83176
A
had he begun
B
he began
C
did he begin
D
began he
推荐题目
Our school has used computers in teaching for ten years. As a result, not only______, but students become more interested in their lessons.
#82767
A
has teachers’ energy been saved
B
saved was teachers’ energy
C
teachers’ energy has saved
D
was saved teachers’ energy
 So loudly _____ that ______ hear her clearly.
#80431
A
did she speak; could everyone
B
did she speak; everyone could
C
she spoke; could everyone
D
she spoke; everyone could
 Doctors have said that as many as 50% of patients don’t take medicine_______. 
#84605
A
like directed
B
to be directed
C
as directed
D
so that directed
—Why do you want the book so much?   —_______, sir. 
#84610
A
Studying
B
Studies
C
Studied
D
To study