Read each sentence. Find the semicolon mistake. Rewrite the sentence

The story has interesting characters, Tom and Luisa, action; and history, a Civil War setting.
The story has interesting characters; Tom and Luisa, action, and history; a Civil War setting.

We finished Chapter 1, Sentences, Chapter 2, Phrases; and Chapter 3, Clauses.
We finished Chapter 1, Sentences; Chapter 2, Phrases; and Chapter 3, Clauses.

The characters are Mary, the nasty girl; Cindy, the kind one, and Tricia, the peacemaker.
The characters are Mary; the nasty girl, Cindy; the kind one, and Tricia; the peacemaker

You should come on Thursday, December 9, Friday, December 17; and Tuesday, December 21.
You should come on Thurdsday, December 9;Friday,December 17; and Tuesday, December 21.

I disagree with your first answer. I think the first sentence is correct.

Your other two are right.

Is the last one right? I posted 4 questions

Sorry -- I can't count. Yes, the last one is right.

The semicolon mistake in the first sentence is that there should be a comma after "action" instead of a semicolon. The correct sentence should be: "The story has interesting characters; Tom and Luisa, action, and history; a Civil War setting."

The semicolon mistake in the second sentence is that there should be a semicolon after "Sentences" instead of a comma. The correct sentence should be: "We finished Chapter 1, Sentences; Chapter 2, Phrases; and Chapter 3, Clauses."

The semicolon mistake in the third sentence is that there should be a semicolon after "Mary" instead of a comma. The correct sentence should be: "The characters are Mary; the nasty girl, Cindy; the kind one, and Tricia; the peacemaker."

The semicolon mistake in the fourth sentence is that there should be a semicolon after "Thursday, December 9" instead of a comma. The correct sentence should be: "You should come on Thursday, December 9; Friday, December 17; and Tuesday, December 21."