Place commas where needed.

7) While I was researching skate
boards, I found an interesting, old newspaper story.
8) In the June 29, 1999, edition of the Mercury, there was an article on skateboarding.
9) Some scientists in San Francisco, California, filmed skateboarders in action.

All are right.

Thanks Ms. Sue! :D

You're welcome.

7) While I was researching skateboards, I found an interesting, old newspaper story.

- The comma is needed after "skateboards" to separate the introductory clause from the main clause.

8) In the June 29, 1999, edition of the Mercury, there was an article on skateboarding.
- The first comma is needed after "1999" to separate the day from the year.
- The second comma is needed after "edition" to separate the date of the edition.

9) Some scientists in San Francisco, California, filmed skateboarders in action.
- The first comma is needed after "San Francisco" to separate the city from the state.
- The second comma is needed after "California" to separate the state from the rest of the sentence.