While watching television, ________. 
#90577
A
the doorbell rang
B
the doorbell rings
C
we heard the doorbell ring
D
we heard the doorbell rings
推荐题目
 ---Do you feel like ____ out? ---No. I’d rather we _______ a taxi.
#95414
A
to drive; take
B
to drive; took
C
driving; take
D
driving; took
When first____ to the market, these products enjoyed great success.
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A
introducing
B
introduced
C
introduce
D
being introduced