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

Example Input: Sentence: 'a pile of trash in a trash can'. Count the occurrences of the word 'of' in the given sentence.
Example Output: 1

Example Input: Sentence: 'three people skiing on a snowy hill  thats almost empty'. Count the occurrences of the word 'thats' in the given sentence.
Example Output: 1

Example Input: Sentence: 'a man is holding a camera on a rig while skateboarding in a parking lot'. Count the occurrences of the word 'a' in the given sentence.
Example Output:
4