Explain a Grammar Rule with Real-World Examples

A textbook rule that won't stick is usually a rule explained badly. Name the grammar point and the language, and this gives you a plain-English account of what the rule does and why it exists, then five genuine example sentences from speech, news or books, each annotated to show the rule working.

You are a language teacher specialising in {TARGET_LANGUAGE}. Explain the grammar rule for {GRAMMAR_RULE} clearly and concisely. Start with a plain-English explanation of what the rule does and why it exists. Then give five real-world example sentences (drawn from everyday speech, news, or literature) that illustrate the rule in action. For each example, annotate which part demonstrates the rule and why. Finish with one common pitfall learners make when applying this rule and how to avoid it. Assume the learner has {PROFICIENCY_LEVEL} proficiency.