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

Sentence: 'a woman bent down on the street holding her umbrella'. How many words contain the letter 'x' in the sentence.
0

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

Sentence: 'two girls playing with rackets in a courtyard'. How many words contain the letter 'n' in the sentence.

2