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

Example Input: Sentence: 'a small dog wearing a bright red bow tie as a collar'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a red plate and a person is decorating a cake'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a plate topped with a frosting covered piece of cake'. Count the occurrences of the word 'piece' in the given sentence.
Example Output:
1