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

Ex Input:
Sentence: 'A person is walking with their dog in a backpack in the park'. Count the number of nouns in this sentence.

Ex Output:
4

Ex Input:
Sentence: 'A boy tucks his knees to complete a jump on his skate board'. Count the number of nouns in this sentence.

Ex Output:
5

Ex Input:
Sentence: 'A dog looking up at a person with a frisbee at their feet'. Count the number of nouns in this sentence.

Ex Output:
4