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

Example Input: Sentence: 'a small child laying in a bed next to a shelf'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a sign for a saab car dealership and cars surrounding it'. Count the occurrences of the word 'sign' in the given sentence.
Example Output: 1

Example Input: Sentence: 'a baseball game is in play while a baseball player is wiping his forhead'. Count the occurrences of the word 'is' in the given sentence.
Example Output:
2