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 man and boy blow out a candle on a birthday cake'. How many words start with the letter 'a' in the sentence.
4

Sentence: 'three chefs talking to each other at a bar'. How many words start with the letter 't' in the sentence.
3

Sentence: 'several sheep are grazing on grass in an open field'. How many words start with the letter 's' in the sentence.

2