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

Input: Consider Input: Sentence: 'a yellow emergency until vehicle in a parking ot'. Count the occurrences of the word 'a' in the given sentence.

Output: 2

Input: Consider Input: Sentence: 'train cars lined up under a bridge full of traffic'. Count the occurrences of the word 'under' in the given sentence.

Output: 1

Input: Consider Input: Sentence: 'a bunch of cupcakes are on a white plate'. Count the occurrences of the word 'a' in the given sentence.
Output: 2