13) Write three sentences, each using a comma in a different way. Then, explain why the comma is needed in each sentence.
1) After finishing the exam, I took a deep breath and felt a wave of relief wash over me.
The comma is needed in this sentence to separate two independent clauses connected by the coordinating conjunction "and". Without the comma, it would create a run-on sentence.
2) Cheese, crackers, and grapes were served as appetizers.
The comma is needed in this sentence to separate items in a list. It helps to clearly distinguish and identify each item being mentioned.
3) The dog, a golden retriever, was extremely friendly.
The comma is needed in this sentence to set off an appositive phrase (a phrase that renames or adds extra information about another noun). In this case, the phrase "a golden retriever" adds extra information about the noun "the dog".