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

Example Input: Sentence: 'a girl sitting on a bench holding a flower'. How many words contain the letter 'p' in the sentence.
Example Output: 0

Example Input: Sentence: 'a beautiful old clock tower in a citys historic district'. How many words contain the letter 'a' in the sentence.
Example Output: 3

Example Input: Sentence: 'a couple of benches sit under an umbrella'. How many words contain the letter 'r' in the sentence.
Example Output:
2