In this task, you need to count the number of times the given letter appears in the given sentence.
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Question: Sentence: 'some sheep are standing in a grassy field'. Find frequency of the letter 'n'

Answer: 3


Question: Sentence: 'a grey hummingbird by fence and tree branches'. Find frequency of the letter 'y'

Answer: 2


Question: Sentence: 'a large airplane flying over a coastal region'. Find frequency of the letter 'v'

Answer:
1