Comma Rules

Which comma rule?

As long as we are back in time, I can go to the movies.

Which comma rule?

Yes, I can do that for you.

Which comma rule:

The desert has a hot, dry climate.

Which comma rule:

Can you grab some coffee before you get here, Karen?

Which comma rule:

Then, you should go to the grocery store.

Which comma rule:

"Hey," the student said. "Can I turn in the assignment for a late grade?"

Which comma rule:

This Saturday, February 21, the band will compete in the marching competition.

Which comma rule:

Jessica bought a shirt, a pair of pants, and a brush.

Which comma rule:

The pizza, in my opinion, is the best I've ever had.

Kelly Clarkson, a singer, was the first person to win American Idol.