**Abstract** can be used in various contexts to describe something as theoretical, conceptual, or not concrete. Here are some examples:
1. The artist created an **abstract painting** that used vibrant colors and geometric shapes to evoke emotions without depicting any specific objects.
2. The professor discussed the **abstract concept** of time in his philosophy class, exploring its nature and different interpretations.
3. The scientist presented an **abstract idea** for a new technology at the conference, describing its potential applications but without going into detailed explanations.
4. The author wrote an **abstract summary** of the research paper, highlighting its main findings and conclusions.
5. The architect designed an **abstract building** with unique and innovative shapes, creating a striking visual impact.
6. The psychologist explored the **abstract thinking** of children, examining how they understand concepts and solve problems.
7. The music composer created an **abstract composition** that used dissonant harmonies and rhythms to challenge listeners' expectations.
8. The historian analyzed the **abstract notion** of freedom in different cultures, examining its meanings and interpretations.
9. The teacher encouraged students to think **abstractly** about mathematical concepts, helping them develop critical thinking skills.
10. The literary critic discussed the **abstract themes** in a novel, analyzing its underlying messages and ideas.