问题
选择题
______, his mother has to take care of him at home.
A．Being ill
B．His to be ill
C．He is ill
D．He being ill
答案
答案：D
题目分析：考查独立主格结构：句意：因为他生病了，他妈妈不得不在家照顾他。逗号后面是句子，中间没有连词，说明前面不是句子，而是独立主格结构：逻辑主语+非谓语，因为he和be ill是主动关系，用现在分词being，选D。