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

Ex Input:
Sentence: 'a red plate and a person is decorating a cake'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
3

Ex Input:
Sentence: 'a plate of ham and rice and a fork on a red tray'. Count the occurrences of the word 'plate' in the given sentence.

Ex Output:
1

Ex Input:
Sentence: 'a man in scrubs looking at a computer'. Count the occurrences of the word 'a' in the given sentence.

Ex Output:
2