Abstract Nouns:
1. Happiness: You can't touch or see happiness, but you can experience it.
2. Freedom: It's an idea or concept, not something you can hold.
3. Courage: A quality or state of mind, not a physical object.
4. Love: A feeling or emotion, not a tangible thing.
5. Justice: A principle or ideal, not a physical entity.
Concrete Nouns:
1. Tree: A physical object you can see and touch.
2. Book: A physical item you can hold and read.
3. Table: A piece of furniture you can sit at.
4. Car: A vehicle you can drive.
5. Rain: A substance you can feel and see.