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

Example Input: Sentence: 'a couple of zebras walk into a open area'. Count the occurrences of the word 'walk' in the given sentence.
Example Output: 1

Example Input: Sentence: 'a cat is sitting near a laptop in a room'. Count the occurrences of the word 'laptop' in the given sentence.
Example Output: 1

Example Input: Sentence: 'someone using a cell phone to do something'. Count the occurrences of the word 'a' in the given sentence.
Example Output:
1