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

Example Input: Sentence: 'a truck and a part of a disabled plane'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'a horse and a dog facing each other in a brown field of grass'. Count the occurrences of the word 'a' in the given sentence.
Example Output: 3

Example Input: Sentence: 'an old town street with people walking around horse drawn carriages and early cars'. Count the occurrences of the word 'drawn' in the given sentence.
Example Output:
1