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

Example Input: Sentence: 'a skateboarder is skating down the street in front of a blue house'. Count the occurrences of the word 'front' in the given sentence.
Example Output: 1

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 man in the living room plays a game on a game system'. Count the occurrences of the word 'a' in the given sentence.
Example Output:
3