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

Sentence: 'a man with two tennis balls and a racket on a tennis court'. Count the occurrences of the word 'a' in the given sentence.
3

Sentence: 'a plate filled with various food items and a carton of milk'. Count the occurrences of the word 'a' in the given sentence.
2

Sentence: 'a giraffe drinking water from a river next to a bush'. Count the occurrences of the word 'a' in the given sentence.

3