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 vase of flowers sitting near a candle on a sink'. Reverse all words of length '6' in the given sentence.
Example Output: a vase of flowers sitting near a eldnac on a sink

Example Input: Sentence: 'a group of zebras gather at a watering hole'. Reverse all words of length '1' in the given sentence.
Example Output: a group of zebras gather at a watering hole

Example Input: Sentence: 'a living room kitchen and stairway to a lower level'. Reverse all words of length '1' in the given sentence.
Example Output:
a living room kitchen and stairway to a lower level