instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a small boat and a large boat on a river near a city'. Find frequency of the letter 'a'
answer:
10


question:
Sentence: 'a piece of bread stuffed with meat and vegetables'. Find frequency of the letter 's'
answer:
2


question:
Sentence: 'a sign that is attached to a wooden board'. Find frequency of the letter 'h'
answer:

2