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

Example Input: Sentence: 'watchful raptor standing on one foot on a rock pile'. How many words contain the letter 'r' in the sentence.
Example Output: 2

Example Input: Sentence: 'a kitchen in a camp with gear and coats laid out'. How many words contain the letter 'i' in the sentence.
Example Output: 4

Example Input: Sentence: 'a man loading luggage onto a machine as it comes off a plane'. How many words contain the letter 'k' in the sentence.
Example Output:
0