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

[Q]: Sentence: 'a man is surfing in a river while another person watches'. Count the occurrences of the word 'a' in the given sentence.
[A]: 2


[Q]: Sentence: 'a person sitting down in front of a couch'. Count the occurrences of the word 'in' in the given sentence.
[A]: 1


[Q]: Sentence: 'a skateboarder grinding a wall on a skateboard'. Count the occurrences of the word 'a' in the given sentence.
[A]:
3