【题目】—What has made him upset recently?
—________ alone to face the troublesome case.
A. Left B. Being left
C. Having left D. To leave
在线课程【答案】B
【解析】
试题分析：考查非谓语动词。句意：是什么让他最近那么不高兴？一个人独自面对这件麻烦事。这句话是一个省略句，答语部分其实是句子的主语，这句话完整的形式是：Being left alone to face a troublesome milk case has made him upset recently.，故选B项。