happening

“There is a lot happening in this town.”
I want to know what is the word - ‘happening’ in this sentence.
Is it adjective or what?
Could you please explain to me so that I can understand correctly?
Thanks.

***** NOT A TEACHER *****

I think (repeat: think) that the following is accurate:

  1. In parsing a “there” sentence, forget the “there.”

  2. ___ is a lot happening in this town.

  3. Now put it in regular order.

  4. A lot IS HAPPENING in this town.

  5. As you can see, “happening” is the present participle in the verb phrase “is happening.”

(Compare: A lot HAPPENS in this town.)

James