Upon their entering the tomb, Carter’s lucky pet bird, which he ____ in Cairo, was swallowed by a snake.
A.was left
B.had left
C.left
D.was leaving
网友回答
B解析考察时态。根据句意可知，leave in Cairo发生在swallow之前，即过去的过去，所以用过去完成时。句意为他们已进入坟墓，Carter的幸运宠物，即他留在开罗的那个，就被一条蛇吞掉了。