________ many times,I still didn't know how to operate the machine.
#91844
A
Having taught
B
Having been taught
C
Being taught
D
Teaching
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Can you imagine _______ alone on the lonely island for ten years?
#96336
A
him to live
B
him lived
C
him living
D
he lives
The policeman warned the drive ________ so carelessly.
#96660
A
never to drive
B
to never drive
C
to not drive
D
doesn’t drive