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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It's dangerous to let the children who are _____ go swimming in the river. 
#94757
A
too young to
B
so young
C
not old enough to
D
so old
 I haven’t seen ________Maggie since I came here.
#92621
A
as lovely a girl as
B
so a lovely girl as
C
girl as lovely as
D
as a lovely girl as
Not until all the fish died in the river      how specious the pollution was. 
#93485
A
did the villagers realize
B
that the villagers realized
C
the villagers did realize
D
didn’t the villagers realize