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

Example Input: Sentence: 'a kitchen with the tiles of a drop ceiling missing'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 2

Example Input: Sentence: 'people standing around on the side the orad with a bus and jeep close to them'. Count the occurrences of the word 'the' in the given sentence.
Example Output: 2

Example Input: Sentence: 'a man picks up a red suitcase near a luggage rack and a silver train is right by the luggage rack'. Count the occurrences of the word 'a' in the given sentence.
Example Output:
4