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

Example Input: Sentence: 'looking out a window at a tall building with a clock on the face'. How many words contain the letter 'l' in the sentence.
Example Output: 4

Example Input: Sentence: 'a group of people dressed to ski standing in the snow'. How many words contain the letter 'b' in the sentence.
Example Output: 0

Example Input: Sentence: 'a stuffed bear standing on top of a bed'. How many words contain the letter 'n' in the sentence.
Example Output:
2