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

Example Input: Sentence: 'a kid is riding a bike down a narrow street'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a black counter top of a stove inside a kitchen'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a picture of a room that has an excellent view of the area'. Count the occurrences of the word 'a' in the given sentence.
Example Output:
2