问题补充：
---Mary, I heard there was an explosion in Luzhou. Could you tell me how it ?
---Sorry, I don’t know much about it either.
A. came on
B. came about
C. came out
D. came over
答案：
A. came on
(答案→)B. came about
C. came out
D. came over
解析：句意：上文，Mary,我听说泸州发生了爆炸。能告诉我是怎么发生的吗？下文，抱歉，我也不了解太多的情况。came on快点 came about发生 came out出现 came over过来，选B。
