Mary clapped her hand over her mouth she realized what she had said.
A. while
B. as soon as
C. suddenly
D. then
网友回答
A. while
(答案→)B. as soon as
C. suddenly
D. then
解析：考查词义辨析。While 当什么时候，as soon as 一……就，suddenly 突然，then 然后，那时，句意：玛丽一意识到她所说的话，她就用手捂住了她的嘴。所以选B。