We cannot figure out ________ quite a number of insects, birds, and animals are dying out.
#73021
A
that
B
as
C
why
D
When
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My father was reading newspapers ____ my mother was cooking at this time yesterday evening.
#41399
A
when
B
which
C
while
D
because
If you feel tired and sick of fat food, that is ______ you have to go to the hospital for medical examination.
#73982
A
why
B
whether
C
when
D
what
The Canadian friends have given us a lot of books, few of _____ a bit difficult for us.
#71881
A
them are
B
that is
C
which are
D
which is
You haven’t answered my question _______ I can join in the game tonight.
#68344
A
if
B
whether
C
which
D
that