TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a herd of horses standing next to each other on a field'. Find frequency of the letter 'r'

SOLUTION: 3

PROBLEM: Sentence: 'a black horse with a white dot on its forehead'. Find frequency of the letter 't'

SOLUTION: 4

PROBLEM: Sentence: 'a man that is sitting down laughing at a girl'. Find frequency of the letter 't'

SOLUTION:
5