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.

Q: Sentence: 'several people are playing frisbee in a park'. How many words start with the letter 'a' in the sentence.

A: 2
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Q: 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.

A: 2
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Q: Sentence: 'a dog sitting on a bench with a field background'. How many words start with the letter 'a' in the sentence.

A:
3
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