Why ____ you keep troubling your mother with such question while he is busy . 
#89771
A
can
B
will
C
would
D
must
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I _____ sooner but I didn’t know that they were waiting for me .
#86796
A
had come
B
was coming
C
would come
D
would have come
 I have lost one of my gloves. I _____ it somewhere. 
#89289
A
must drop
B
must have dropped
C
must be dropping
D
must have been dropped
 Imagine what today’s life would be like if Alexander Bell _____ the telephone more than 130 years ago!
#87256
A
didn’t invent
B
wouldn’t invent
C
hadn’t invented
D
wouldn’t have invented