A good example is the phrases "what a sight!" and "what a view!". "what a sight!"- this means whatever you saw was very strange, unusual, or unexpected. It can refer to a thing, or an action, and can (but not always) means it wasn't a good thing that you saw. "what a view!"- this means whatever you saw was beautiful, and almost always refers to a landscape (que un visto)

A 'sight' is anything which you can see - a place, a person, an object - anything at all. It can also refer to the sense eg Grandma is blind - she lost her sight years ago A 'view' is mainly used for places, and it refers to what you can see from a particular point. It's often used for landscape and scenery eg you can buy postcards of views of a town. You might say 'There's a lovely view of the sea from the top floor of the house' , or say 'Go over there to take your photo - the view is much better'. View can also mean an opinion ie your point of view.