In this task, you need to count the occurrences of the given word in the given sentence.

Sentence: 'a man on a motorcycle riding by an old rundown town and an animal on the side of the road'. Count the occurrences of the word 'on' in the given sentence.
2

Sentence: 'a little girl holds a tooth brush while her mother stands in the background in a bathroom'. Count the occurrences of the word 'while' in the given sentence.
1

Sentence: 'a hot dog on a bun in a wrapper'. Count the occurrences of the word 'a' in the given sentence.

3