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

Example Input: Sentence: 'two pieces of luggage are sitting on the shelf'. Count the occurrences of the word 'two' in the given sentence.
Example Output: 1

Example Input: Sentence: 'several boats parked near the rivers edge letting passengers off'. Count the occurrences of the word 'rivers' in the given sentence.
Example Output: 1

Example Input: Sentence: 'picture of a tab tub where the wall is open exposing wood studs and a shop vacuum is in the tub'. Count the occurrences of the word 'tub' in the given sentence.
Example Output:
2