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.

Example Input: Sentence: 'a vase filled with white flowers sitting on top of a wooden table'. How many words start with the letter 't' in the sentence.
Example Output: 2

Example Input: Sentence: 'a tennis player swings his racket on a serve'. How many words start with the letter 'o' in the sentence.
Example Output: 1

Example Input: Sentence: 'the toilet is empty and the seat is up'. How many words start with the letter 't' in the sentence.
Example Output:
3