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

Example Input: Sentence: 'A man riding on the back of an elephant near a lake'. Count the number of nouns in this sentence.
Example Output: 4

Example Input: Sentence: 'A boy holds a white frisbee with a purple paw print on it'. Count the number of nouns in this sentence.
Example Output: 4

Example Input: Sentence: 'A soccer player kicking a soccer ball on the soccer field'. Count the number of nouns in this sentence.
Example Output:
6