问题补充：
In the darkness, she felt , but when she turned around, nobody was there.
A. to follow
B. following
C. to be followed
D. being followed
答案：
A. to follow
B. following
C. to be followed
(答案→)D. being followed
解析：“feel感觉到”后面要跟v-ing形式。有人跟着她，即她被人跟着。故要用动名词的被动式。句意：黑暗中，她感到身后有人跟着，但是等她转过头来看时，却没有人。
