问题
选择题
Many human activities also _______carbon gases, which will result in global warming.
A.put off
B.send off
C.let off
D.set off
答案
答案:C
题目分析:考查词组:A. put off推迟,B. send off为…送行,寄出,发出,派往C. let off释放,D. set off出发,引发,引爆,句意:很多人类的活动也释放出二氧化碳,这导致全球气温变暖。选C。