--- I called you last night, but no one answered.
--- Sorry, I _______ sleeping.
A.must have been
B.would have been
C.must be
D.could be
The tea-picking opera _____ developed from the tea-growing regions in Jiangxi where the tea pickers would sing songs while working.
A.luckily B.skillfully C.originally D.rapidly
It was the middle of the night _______ the sound of the piano woke me up.
A.because
B.if
C.that
D.when
Dennis turned up at the hospital ________ gifts for the new mother Lindsey and her baby, who appreciated his visit and good will.
A.bearing
B.collecting
C.opening
D.making
What difficulty _____you have ______the problem?
A. you think; solving B. do you think; to solve
C. do you think; solving D. you think; to solve
I had no idea that one simple comment would ________ such a huge argument.
A.go out
B.go off
C.set out
D.set off