are used in a list, before conjunctions, after introductory phrases, to set off phrases describing a noun, to set off parenthetical expressions, to separate items in dates and addresses, and after salutation or closing of a friendly letter.
either combine 2 or more words into a contraction or show possession
Underlining or Italicizing
used for book titles, movies, and TV shows
is added at the end of a word
express one complete thought
combine one complete thought with one that is not complete
2 or more complete thoughts with 1 or more that is not complete.