instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'two men are playing a video game as another sits watching'. Find frequency of the letter 'a'
answer:
7


question:
Sentence: 'a black computer with a screen reading "press any key to begin."'. Find frequency of the letter 'a'
answer:
5


question:
Sentence: 'a group of buses in the street near buildings and a group of people'. Find frequency of the letter 'i'
answer:

3