55. All students in the class a loud laugh when the professor told them a joke.(A) let up(B) let dow

問題詳情

55. All students in the class a loud laugh when the professor told them a joke.
(A) let up
(B) let down
(C) let off
(D) let out

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