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

Example Input: Sentence: 'An oriental musical group gathered in a field'. Count the number of nouns in this sentence.
Example Output: 2

Example Input: Sentence: 'a person eating a hot dog next to other people'. Count the number of nouns in this sentence.
Example Output: 3

Example Input: Sentence: 'Black dog in a mowed field returning a frisbee to the thrower'. Count the number of nouns in this sentence.
Example Output:
4