問題詳情

31 , in the United States, that toothbrushes made of synthetic nylon were introduced.
(A) It wasn’t until 1938
(B) Until 1938
(C) It was until 1938
(D) Being in 1938

參考答案

答案：A
難度：困難0.305556
統計：A(11),B(11),C(9),D(5),E(0)