_______cloning human embryos is not legal in many countries, some scientists are already pushing ahead with research in order to produce a cloned human baby.
#31691
A
While
B
When
C
Since
D
if only
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Livemocha.com is a free site ______visitors can not just learn various languages but also chat online.
#30884
A
where
B
which
C
that
D
what
It was 1995 __________ we began to develop the new computer system.
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A
when
B
which
C
since
D
that
I don’t think Susan will be sad but I’ll go and comfort her ______ she is.
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A
in case
B
even though
C
as if
D
unless
He made a mistake, but then he corrected the situation ________ it got worse.
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A
until
B
when
C
before
D
as