, 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
网友回答
A. Being ill
B. His to be ill
C. He is ill
(答案→)D. He being ill
解析：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。