instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'two zebra stand near the wooden posts on a building'. Find frequency of the letter 't'
answer:
4


question:
Sentence: 'a guy surfs a wave with his surfboard'. Find frequency of the letter 's'
answer:
4


question:
Sentence: 'a red and white sign reading "whoa" and a red a white sign reading "caution children at play"'. Find frequency of the letter 't'
answer:

4