instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'some sheep are standing in a grassy field'. Find frequency of the letter 'n'
answer:
3


question:
Sentence: 'a woman throwing a frisbee on a field'. Find frequency of the letter 's'
answer:
1


question:
Sentence: 'a man with a hat skiing with skis and ski poles'. Find frequency of the letter 'g'
answer:

1