19._________comfortably in a chair,he was completely lost in a magazine

问题描述:

19._________comfortably in a chair,he was completely lost in a magazine
20._______ comfortably in a chair,he was completely lost in a magazine.
A.To sit B.Sat C.Sitting D.Having sat

选C
这里是动词的现在分词作伴随状语.
“坐在椅子上”与主语“他”是主动关系.所以不用B.B表被动.
ATo sit 表目的或表将来.所以排除A.
DHaving sat 是表完成时.