题目内容：

I found mary ( )her room this morning
括号中填clean的适当形式

优质解答

I found Mary 【cleaning】her room this morning.
翻译：今早上,我发现Mary正在打扫她的房间.
find sb doing sth 意思是“看见某人正在做.” 是现在分词做宾补的用法.
The boy has a lot of fun 【in speaking】English.