Newton was sitting under an apple tree ______ an apple fell onto his head. 
#92858
A
when
B
while
C
after
D
before
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________ some of the orange juice and perhaps you will like it.
#95168
A
Trying
B
Try
C
To try
D
Have tried
________ something wrong with the machine, I am afraid.
#94080
A
There seems to have
B
There seems to be
C
He seems to be
D
It seems to be
--- Perhaps John’s not in.    --- _______. Look, the light is on.
#93597
A
Yes, he can be at home.
B
No, he couldn’t go out
C
Yes, he must be at home
D
No, he needn’t go out