问题补充:
Our earth is getting warmer and warmer. It is time for us to the emission(排放) of CO2.
A. break down
B. cut in
C. cut down
D. cut off
答案:
A. break down
B. cut in
(答案→)C. cut down
D. cut off
解析:考查短语辨析。A. break down抛锚;B. cut in插嘴;C. cut down消减;D. cut off切断。句意:我们的地球变得越来越暖,是该我们消减二氧化碳排放的时候了。故C正确。