Here are the rules when you use commas, ellipses and dashes
commas- when you list things. I like apples, oranges, and bananas.
after a greeting of a letter. Dear Mr. Jones,
connects 2 clauses. I like chocolate, but I prefer vanilla.
ellipses- connects to thoughts in the same sentence.
If she had . . . it doesn't matter now.
dashes- Connects two ideas. There is a rare species of birds in Asia---it is yellow.
commas- when you list things. I like apples, oranges, and bananas.
after a greeting of a letter. Dear Mr. Jones,
connects 2 clauses. I like chocolate, but I prefer vanilla.
ellipses- connects to thoughts in the same sentence.
If she had . . . it doesn't matter now.
dashes- Connects two ideas. There is a rare species of birds in Asia---it is yellow.