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: 'young boy flying kite in large field at outdoor event'. Find frequency of the letter 'y'

Answer: 3

Question: Sentence: 'a silver train crossing the road on tracks'. Find frequency of the letter 'r'

Answer: 5

Question: Sentence: 'a woman stands behind her luggage with her turtle neck pulled halfway over her face'. Find frequency of the letter 'f'

Answer:
2