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

Example Input: Sentence: 'a man is riding a red motorcycle on the street'. Count the number of nouns in this sentence.
Example Output: 3

Example Input: Sentence: 'A tray with a doughnut and a cup of coffee on it'. Count the number of nouns in this sentence.
Example Output: 4

Example Input: Sentence: 'A man flying through the air while riding skis'. Count the number of nouns in this sentence.
Example Output:
3