問題詳情

20、 Unpredictable temperatures, short growing seasons, and heavy snows prevent _____ at highelevations.
(A) grow trees
(B) the growth of trees
(C) trees are growing
(D) and growth of trees 

參考答案

答案：B
難度：簡單0.872727
統計：A(1),B(48),C(4),D(2),E(0)