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

Example Input: Sentence: 'an elephant that is eating some leaves from a tree'. How many words contain the letter 'n' in the sentence.
Example Output: 3

Example Input: Sentence: 'a dog lying down with a blanket on top of it'. How many words contain the letter 'o' in the sentence.
Example Output: 5

Example Input: Sentence: 'a man skating across a crosswalk with his skateboard'. How many words contain the letter 'l' in the sentence.
Example Output:
1