Recognize an abstract noun when you see one.
Nouns name people, places, and things. One class of nouns is abstract. Your five senses cannot detect this group of nouns. You cannot see them, hear them, smell them, taste them, or feel them.
When Joseph dived into the violent waves to rescue a drowning puppy, his bravery amazed the crowd of fishermen standing on the dock.
Bravery, one of the nouns in this sentence, is an example of an abstract noun. You can see Joseph, the water, and the crowd. But you cannot see braveryitself. Bravery has no color, size, shape, sound, odor, flavor, or texture; it has no quality that you can see, hear, smell, taste, or touch. Any noun that escapes your five senses is an abstract noun.
Many nouns are concrete, not abstract. Concrete nouns register on your five senses. Here is an example:
Joseph cuddled the wet puppy under his warm jacket.
Puppy is an example of a concrete noun. You can see a puppy, stroke its fur, smell its breath, and listen to it whine. You can even taste the puppy if you don't mind pulling dog hair off your tongue! Because a puppy will register on all five senses,puppy is a concrete noun.
Look over this chart contrasting abstract and concrete nouns: