問題詳情
20. Sunburn, __________ , is caused by ultraviolet rays.
(A)an inflammation of the skin
(B)is an inflammation of the skin
(C)that an inflammation of the skin is
(D)when there is an inflammation of the skin
參考答案
答案：A
難度：簡單0.826087
統計：A(19),B(2),C(2),D(0),E(0)