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

Example Input: Sentence: 'the table  in the apartment is set for two to have cake and a doll is seated in one chair'. Count the occurrences of the word 'is' in the given sentence.
Example Output: 2

Example Input: Sentence: 'a desktop computers sitting on a desk next to a laptop'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a person surfs on a wave in a body of water'. Count the occurrences of the word 'a' in the given sentence.
Example Output:
3