31. Mike stared at the sky, _____ what to do. (A) not to know (B) to not knowing (C) to not know (D)

問題詳情

31. Mike stared at the sky, _____ what to do.
(A) not to know
(B) to not knowing
(C) to not know
(D) not knowing

答案：D
難度：適中0.5
統計：A(4),B(1),C(2),D(8),E(0)