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

Input: Consider Input: Sentence: 'a snowboarder in a gray jacket is doing a trick'. Count the occurrences of the word 'a' in the given sentence.

Output: 3

Input: Consider Input: Sentence: 'a bathroom with a vanity mirror toilette and kitchen sink next to a shower'. Count the occurrences of the word 'a' in the given sentence.

Output: 3

Input: Consider Input: Sentence: 'a wooden pedestrian sign mounted in a downtown setting'. Count the occurrences of the word 'sign' in the given sentence.
Output: 1