Scientists say it may be five or six years _____ it is possible to test this medicine to human patients.
#92420
A
since
B
after
C
before
D
when
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 We all think it most foolish ________ such a mistake .
#92392
A
for you making
B
of you to make
C
you to make
D
for you to make
.Only when you ________can you earn a living, .
#94231
A
settle down
B
takes a risk
C
react to
D
cheer on
--- 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