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

Example Input: Sentence: 'a stuffed animal sits in front of a sheet'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 2

Example Input: Sentence: 'a person wearing a suit and tie next to a woman in a dress'. Count the occurrences of the word 'tie' in the given sentence.
Example Output: 1

Example Input: Sentence: 'a red car sitting on to of a black boat'. Count the occurrences of the word 'a' in the given sentence.
Example Output:
2