________ repeatedly, the problem still appeared in the beginners’ homework.
#100762
A
Explaining
B
Having explained
C
Having been explained
D
To be explained
推荐题目
The robber would ____ to 7 years in _____ prison.
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A
sentence; /
B
be sentenced; /
C
be sentenced; the
D
sentence ; the
Mr Smith suggested the problem worth paying attention to ________ at the meeting. 
#104578
A
should discuss
B
was discussed
C
being discussed
D
be discussed