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

Example Input: Sentence: 'man extending arm with three bananas crosswise on it'. Reverse all words of length '4' in the given sentence.
Example Output: man extending arm htiw three bananas crosswise on it

Example Input: Sentence: 'a slice of pizza is sitting on the top of a paper plate'. Reverse all words of length '5' in the given sentence.
Example Output:
a ecils of azzip is sitting on the top of a repap etalp