instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a dog laying on the back of a boat in the water'. Find frequency of the letter 't'
answer:
4

question:
Sentence: 'a couple of men sitting next to each other under an umbrella'. Find frequency of the letter 'n'
answer:
5

question:
Sentence: 'men working in a restaurant kitchen at an island'. Find frequency of the letter 'i'
answer:
4