He was deep in thought with his eyes on the ceiling.A. fixedB. fixingC. fixD. to be fixing

问题补充：

He was deep in thought with his eyes on the ceiling.

A. fixed

B. fixing

C. fix

D. to be fixing

答案：

(答案→)A. fixed

B. fixing

C. fix

D. to be fixing

解析：考查with+n.+doing 复合结构。Fix one’s eyes on结构中名词和动词之间为被动关系，凝视-----，为固定短语，故用fixed。