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

Example Input: Sentence: 'a cat that is laying down on a bed'. Count the occurrences of the word 'is' in the given sentence.
Example Output: 1

Example Input: Sentence: 'two zebras in a dirt field looking for food'. Count the occurrences of the word 'for' in the given sentence.
Example Output: 1

Example Input: Sentence: 'a group of people standing in a street'. Count the occurrences of the word 'of' in the given sentence.
Example Output:
1