_________several times, but Mary still has no idea of how to do it properly. 
#19683
A
Being shown
B
Having shown
C
Having been shown
D
I’ve shown her
推荐题目
You can see the stars on a clear night, but in the daytime they are ____ .
#20539
A
unavoidable
B
invisible
C
inaccessible
D
unavailable
This year they have produced_________ they produced the year before last.
#19899
A
twice many cars as
B
twice as many cars as
C
twice more than cars
D
twice the cars of