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.
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Question: Sentence: 'two couples sit on a bench in front of bushes with pink flowers'. How many words start with the letter 'o' in the sentence.

Answer: 2


Question: Sentence: 'two men are riding horses on a beach'. How many words start with the letter 'r' in the sentence.

Answer: 1


Question: Sentence: 'a man sitting on a park bench playing a guitar'. How many words start with the letter 'a' in the sentence.

Answer:
3