| A | B |
| John's friend is funny, but his brother is very serious. | Compound sentence - , but - |
| Sam rarely works and he gets mad when someone says something to him. | run-on sentence - need to add a comma after works |
| Sarah and Sam are best friends, but they are in different classes. | Compound sentence - , but |
| The puppies are so cute and soft and they look so sweet sleeping. | Run-on sentence - add a comma "soft" |
| I love going to the movies but sometimes, I can't go because I have spent all of my money. | Run-on sentence - add a perios after movies and capitalize the "S" in "Sometimes." |
| I love chocolate cupcakes, but my favorite cupcake is vanilla bean cupcakes. | Compound sentence - , but |
| Nathaniel Bacon was a traitor to his country but no one remembers him but they remember John Booth. | Run-on sentence - add a comma after country, add a period after remembers him, and capitalize the "t" in "They." |
| I like sweet and crisp apples, but oranges are my favorite. | Complete sentence - , but |
| Sam and John went to the same coding club after school, and they both have coding class in school. | Complete sentence - , ang |
| Many people enjoy writing but they don't like editing their work. | Run-on sentence - add a comma after "writing" |