问题
选择题
---What on earth are the police busy with?
---They have been looking into how the plane crash _______.
A．came out
B．came up
C．came down
D．came about
答案
答案：D
词义辨析。came out出现,出版,结果是came up；提出来(流行,走近,来临,上,升)；came down下来，下落； came about发生。他们一直在调查坠机事件是怎么发生的？选D。