TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a person that is looking out his window'. Find frequency of the letter 'n'

SOLUTION: 3

PROBLEM: Sentence: 'a bed with a dog laying on it next to two laptop computers'. Find frequency of the letter 'n'

SOLUTION: 3

PROBLEM: Sentence: 'two elephants in the field close to some building structures'. Find frequency of the letter 'i'

SOLUTION:
4