the front door , he had to enter the room through the back door.
A. Seen; painted
B. Seeing; painted
C. Being seen; being painted
D. Seeing; being painted
网友回答
A. Seen; painted
B. Seeing; painted
C. Being seen; being painted
(答案→)D. Seeing; being painted
解析：see 表示的动作与句子谓语动词（had to enter）所表示的动作几乎同时发生，且与其逻辑主语（he）为主动关系，故用一般式。由句意“看到前门正在被漆，……”可知，第二空应用being painted。