As the sea ice melts sooner each swimmer,polar bears are forced to come ashore earlier and face food shortages _____ they have stored enough fat to last them through the season.
#31875
A
before
B
unless
C
since
D
until
推荐题目
I was excited ＿＿ I came to this school.
#31705
A
for the first time
B
the first time
C
at first
D
the first time when
Find ways to praise your children often，________ you'll find they will open their hearts to you.(2011·山东)
#30481
A
till
B
or
C
and
D
but
________ nearly all behavior is learned behavior is a basic assumption ________ has been put forward by social scientists.
#30076
A
What; that
B
That; what
C
What; what
D
That; that
He is so busy. He cannot afford enough time with his son ____he wants to.
#30950
A
even if
B
as if
C
because
D
before