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: 'the woman is standing in the rain with her umbrella'. How many words start with the letter 't' in the sentence.
Example Output: 2

Example Input: Sentence: 'a woman walks in the street in the rain'. How many words start with the letter 'i' in the sentence.
Example Output: 2

Example Input: Sentence: 'a very nice building and a car moving through a zebra crossing'. How many words start with the letter 'c' in the sentence.
Example Output:
2