問題詳情

34. Sales of CDs have greatly increased since the early 1990s, when people__b___to enjoy the advantages of this new technology.
(A) begin
(B) began
(C) have begun
(D) had begun

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)