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.
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Question: Sentence: 'a man in a blue shirt is playing tennis'. Reverse all words of length '3' in the given sentence.

Answer: a nam in a blue shirt is playing tennis


Question: Sentence: 'a small child having his teeth brushed by an adult'. Reverse all words of length '7' in the given sentence.

Answer: a small child having his teeth dehsurb by an adult


Question: Sentence: 'many cows on a field of grass with trees in the background'. Reverse all words of length '1' in the given sentence.

Answer:
many cows on a field of grass with trees in the background