In this task, you need to count the number of nouns/verbs in the given sentence.

Example Input: Sentence: 'A woman riding a surfboard on top of a wave in the ocean'. Count the number of verbs in this sentence.
Example Output: 1

Example Input: Sentence: 'The players are playing a game of Frisbee on the grass'. Count the number of verbs in this sentence.
Example Output: 1

Example Input: Sentence: 'A sign on a sidewalk reads "STOP Engraving in process"'. Count the number of verbs in this sentence.
Example Output:
2