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

Example Input: Sentence: 'a train on the side of a road on the edge of the water'. How many words contain the letter 'u' in the sentence.
Example Output: 0

Example Input: Sentence: 'this is a yellow train riding the rails'. How many words contain the letter 'n' in the sentence.
Example Output: 2

Example Input: Sentence: 'vulture swooping down toward the ground in landscape'. How many words contain the letter 'o' in the sentence.
Example Output:
4