What Herbert ??? (Unnecessary)
I would say warriors as common noun refers to a concept to a particular individual .
If we look at the part of the sentence "when a football practice was over" we can say that it is a recurring action periodically and it represents a routine, but that's not a phrase because it is stated specifically, what is the issue. "I stopped" also suggests a concrete action, therefore, it's not a phrase, because it explicitly indicates what has been done. What is the phrase in this sentence is a cluster of words without a finite verb, and having that in mind, the correct answer is "riding a skateboard".
If the question is 2x > 18, then all you have to do is divide. And when you divide 18/2, x is equal to 9. I'm not sure if that is one of the choices, but I believe that's how you do it...
