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

Example Input: Sentence: 'a scene of a person in a baseball game'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a blue boat is up on blocks at a dock'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 2

Example Input: Sentence: 'a young boy in traditional clothing holding a fan and a cell phone'. Count the occurrences of the word 'boy' in the given sentence.
Example Output:
1