When do writers need to use a conjunction? when they need to explain where something happened
when they need to be more specific about a noun
when they need to show what an action looked like
when they need to connect—or join—two ideas

when they need to connect—or join—two ideas

Explanation:

Writers need to use a conjunction in order to connect two ideas together. There are mainly four types of conjunctions: Coordinating conjunctions, Correlative conjunctions, Conjunctive Adverbs and Subordinating conjunctions.

Using these different conjunctions allow the writers' thoughts to be well-delivered and understood by the reader smoothly. It also allows him to create better sentences. It is important for the writer to know how to use these conjunctions properly in order to prevent incoherent sentences.

THIS A OTHER GUYHS answer but here :The description during the horse race improves the scene by making me feel as though I am in the action and experiencing events at the same time Paul is. I can see Paul taking note of what is around him as he and the grey pass one horse at a time. The description of the horse sizzling like lightning makes Paul's win seem really exciting.

Explanation: