What are the verbals in these sentences and are they gerunds or participles?

Question

The dog reacted by racing around the corner, dashing across the kitchen, and skidding to a stop.

In the finished commercial, the chuck wagon disappears right through the cabinet door.

Answer 1

Racing, dashing, skidding are all gerunds -- objects of the preposition "by."

What do you think "finished" is?

Answer 2

I think finished is a verbal and a gerund because you can replace it with a noun?

What about this one?
The trainer aroused yearning in the dog by hiding a squeaky toy in a closet.

yearning a gerund and hiding a gerund?

Answer 3

With what noun would you replace "finished?"

Your last answers are correct. Both are gerunds.

Answer 4

Study this site.

http://www.chompchomp.com/terms/gerund.htm

Answer 5

Thanks does help. Confused still with

In the finished commercial, the chuck wagon disappears right through the cabinet door.

In is a preposition so gerund? or describes commercial so participle?

Answer 6

You missed an important fact about gerunds. Please read the site I posted for you.