looking (look的现在分词);用于现在进行时.
例:
Why is he looking so sad?
他为何看上去如此凄伤?
What is he looking at,then?
那么他到底是在看什么?
He is looking at someone.
他正在看着某个人.
looked (look过去式,过去分词)用于一般过去式
例:
They looked at each other.
他们目光相互对视.
She looked in on her friend on her way home
她在回家的路上顺便看看朋友.