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

Example Input: Sentence: 'a woman with a walker is sitting on a park bench'. Count the occurrences of the word 'with' in the given sentence.
Example Output: 1

Example Input: Sentence: 'a person doing a jump on a snowboard'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a city traffic light is red with a large billow of smoke in the background'. Count the occurrences of the word 'a' in the given sentence.
Example Output:
2