問題詳情
10. The greenhouse effects occurs ____ heat radiated from the sun.
(A) when does the earth’s atmosphere trap
(B) does the earth’s atmosphere trap
(C) when the earth’s atmosphere traps
(D) the earth’s atmosphere trap
參考答案
答案：C
難度：簡單0.854962
統計：A(6),B(2),C(112),D(5),E(0)