Respuesta :

Answer:

Run-on

Explanation:

If you read it aloud, you will notice that it doesn't sound right because there should be a period after high school. Or at least a comma after school to for a pause        

Answer:

Run-on

Explanation:

The sentence "My grandpa never graduated from highschool" can stand on its own, and so can "He started his own business at the age of fifteen."