问题
选择题
The greenhouse effect comes into being because of too much _______ in space. [ ]
A. ozone
B. carbon dioxide
C. carbon oxide
D. oxygen
答案
答案：B
搜题请搜索小程序“爱下问搜题”
The greenhouse effect comes into being because of too much _______ in space. [ ]
A. ozone
B. carbon dioxide
C. carbon oxide
D. oxygen
答案：B