In this task, you need to count the number of words in a sentence that contain the given letter

Ex Input:
Sentence: 'person standing in the grass striking a baseball with a bat'. How many words contain the letter 's' in the sentence.

Ex Output:
5

Ex Input:
Sentence: 'a man that is sitting at a table with a bowl'. How many words contain the letter 'k' in the sentence.

Ex Output:
0

Ex Input:
Sentence: 'a few birds walking along an alley way'. How many words contain the letter 's' in the sentence.

Ex Output:
1