你说的这种情况是现在分词作后置定语如
The boy standing at the door is my brother.现在分词作后置定语表示和被修饰词之间的主动关系.
=The boy who is standing at the door is my brother.
下面这几个也是作定语的非谓语动词,注意它们的区别.
the food bought in this supermarket is good.bought in this supermarket与被修饰词之间是被动关系.
=the food which/that was bought in this supermarket is good.