In this task, you need to count the number of words in a sentence that start with the given letter. Answer with numbers and not words.

Sentence: 'a colorful sculpture of an elephant in a park'. How many words start with the letter 'a' in the sentence.
3

Sentence: 'a person sitting on a stone wall using a cellular phone'. How many words start with the letter 's' in the sentence.
2

Sentence: 'a group of people stand in front of boxes of pizza while eating slices of pizza'. How many words start with the letter 's' in the sentence.

2