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: 'the cox is standing behind the fence alone'. Reverse all words of length '2' in the given sentence.
Example Output: the cox si standing behind the fence alone

Example Input: Sentence: 'competitor preparing to return volley during major tennis tournament'. Reverse all words of length '6' in the given sentence.
Example Output: competitor preparing to nruter yellov gnirud major sinnet tournament

Example Input: Sentence: 'a shirtless man lays on a bed and smiles'. Reverse all words of length '9' in the given sentence.
Example Output:
a sseltrihs man lays on a bed and smiles