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: 'there is a group of people standing on the beach'. Reverse all words of length '8' in the given sentence.
Example Output: there is a group of people gnidnats on the beach

Example Input: Sentence: 'a girl in a wig holding a tennis racket'. Reverse all words of length '3' in the given sentence.
Example Output: a girl in a giw holding a tennis racket

Example Input: Sentence: 'a woman preparing food inside of a kitchen'. Reverse all words of length '4' in the given sentence.
Example Output:
a woman preparing doof inside of a kitchen