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 beach chair and sandals in the sand'. Reverse all words of length '2' in the given sentence.
Example Output: a beach chair and sandals ni the sand

Example Input: Sentence: 'three cows graze on the food that sits just outside their pens'. Reverse all words of length '5' in the given sentence.
Example Output: eerht cows ezarg on the food that sits just outside rieht pens

Example Input: Sentence: 'a man riding a very tall bike past a very tall pole'. Reverse all words of length '6' in the given sentence.
Example Output:
a man gnidir a very tall bike past a very tall pole