Grammar Lesson Generator

I'm learning [TARGET LANGUAGE] at a [BEGINNER/INTERMEDIATE/ADVANCED] level. Please create a detailed grammar lesson on: [GRAMMAR TOPIC]

Include:
1. Clear explanation of the grammar rule
2. When and why this grammar is used
3. Formation/structure with formulas
4. 10 example sentences with translations
5. Common exceptions and irregular cases
6. Common mistakes learners make
7. Comparison with English (if applicable)
8. Practice exercises (5 fill-in-the-blank, 5 sentence transformation)
9. Answer key with explanations