David didn’t give up ______ he had failed in the experiment four times.
#57729
A
if
B
while
C
though
D
since
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________ I got on the bus, he got off.
#55991
A
As
B
While
C
Until
D
Till
If I ______ five minutes, I will get everything ready. 
#57664
A
will give
B
be given
C
am given
D
was given
 Mary sings English songs well and ______.
#55513
A
Jane does too
B
either does Joes
C
so Janes does
D
so does Jane