instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'an image of a street sign with a corner restaurant'. Find frequency of the letter 'u'
answer:
1


question:
Sentence: 'a child sitting a table with a pizza in front of him'. Find frequency of the letter 'h'
answer:
3


question:
Sentence: 'a passenger train that is pulling into a station'. Find frequency of the letter 's'
answer:

4