問題詳情

19. __________ dinosaurs died out remains an unsolved mystery.
(A) All
(B) Why
(C) While
(D) Thatร 3 ଄Δ٥ 4 ଄

參考答案

答案:[無官方正解]
難度:適中0.5
統計:A(0),B(0),C(0),D(0),E(0)