問題詳情

33. The flu is believed _______ by viruses that like to reproduce in the cells inside the human nose and throat.
(A). causing
(B). being caused
(C). to be caused
(D). be have caused

參考答案

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