15．– How cold it is! I wonder how grass survive under such heavy snow．
--Don’t worry．There is a lot of air in loose snow which ．
A. keeps out the cold
B. keeps the cold away
C. keep off the cold
D. keep the cold up
网友回答
(答案→)A. keeps out the cold
B. keeps the cold away
C. keep off the cold
D. keep the cold up
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