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 large bathroom with double sinks and a walk in shower'. How many words start with the letter 'a' in the sentence.
Example Output: 3

Example Input: Sentence: 'a large group of motorcyclists waiting in the street'. How many words start with the letter 'g' in the sentence.
Example Output: 1

Example Input: Sentence: 'two horses walking in the dirt near a wooden fence'. How many words start with the letter 't' in the sentence.
Example Output:
2