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 man assisting a person on a horse on a race track'. Reverse all words of length '3' in the given sentence.
[A]: a nam assisting a person on a horse on a race track


[Q]: Sentence: 'three house cats look outside from a window'. Reverse all words of length '1' in the given sentence.
[A]: three house cats look outside from a window


[Q]: Sentence: 'a hot dog with ground beef onions and mustard on top of it'. Reverse all words of length '7' in the given sentence.
[A]:
a hot dog with ground beef onions and dratsum on top of it