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.

Example Input: Sentence: 'an elderly man in a jacket is walking outside of a window'. Reverse all words of length '3' in the given sentence.
Example Output: an elderly nam in a jacket is walking outside of a window

Example Input: Sentence: 'the bathroom has a toilet a window and a sink'. Reverse all words of length '8' in the given sentence.
Example Output: the moorhtab has a toilet a window and a sink

Example Input: Sentence: 'a couple of toothbrushes that are on a towel'. Reverse all words of length '6' in the given sentence.
Example Output:
a elpuoc of toothbrushes that are on a towel