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: 'a crowd of people standing in front of a green train'. Find frequency of the letter 'g'

Answer: 2


Question: Sentence: 'people playing wii bowling in a modern library'. Find frequency of the letter 'o'

Answer: 3


Question: Sentence: 'a woman is pouring a large amount a wine into glasses'. Find frequency of the letter 'a'

Answer:
7