In English Common Core L.3.1.h, students learn about using coordinating and subordinating conjunctions in sentences. This involves understanding various conjunctions and how they can be employed to connect words, phrases, and clauses, ultimately enhancing the complexity and variety of their writing and speech. They also master the skill of using these conjunctions to express more complex ideas or combine multiple ideas in a single sentence. This standard enhances logical thinking and improves writing and reading comprehension skills.