In this task, you need to reverse all words of a given length in the sentence. The number of letters in a word determine its length. For example, the length of the word "apple" is 5.

Q: Sentence: 'a dog lays next to a bag on a couch'. Reverse all words of length '4' in the given sentence.

A: a dog syal txen to a bag on a couch
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Q: Sentence: 'reflection of window on mirror in dark bathroom'. Reverse all words of length '10' in the given sentence.

A: noitcelfer of window on mirror in dark bathroom
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Q: Sentence: 'the tennis player is serving a tennis ball'. Reverse all words of length '1' in the given sentence.

A:
the tennis player is serving a tennis ball
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