問題詳情

【題組】61. Sand dunes are formed when______a_____________.
(A) sand piles up gradually
(B) there is plenty of rain in a year
(C) the sea has dried up over the years
(D) pieces of rock get smaller

參考答案

答案：A
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)