問題詳情

62. It may be necessary to stop ________ in the learning process and go back to the difficult points in the lessons.
(A) at a distance
(B) at intervals
(C) at case
(D) at length

參考答案

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