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

Input: Consider Input: Sentence: 'a group of people skiing down a mountain slope'. How many words contain the letter 'e' in the sentence.

Output: 2

Input: Consider Input: Sentence: 'some brown and white goats and a man on some grass'. How many words contain the letter 'o' in the sentence.

Output: 5

Input: Consider Input: Sentence: 'a group of men riding skis across snow covered country'. How many words contain the letter 'r' in the sentence.
Output: 5