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

Example Input: Sentence: 'Two people riding a surfboard in the open waves'. Count the number of nouns in this sentence.
Example Output: 3

Example Input: Sentence: 'A black horse that is tied up eating grass'. Count the number of nouns in this sentence.
Example Output: 2

Example Input: Sentence: 'A person is swinging a tennis racket at a ball on a court'. Count the number of nouns in this sentence.
Example Output:
5