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 in a blue shirt is playing tennis'. Reverse all words of length '3' in the given sentence.
Example Output: a nam in a blue shirt is playing tennis

Example Input: Sentence: 'four cute little ducklings swimming in the water'. Reverse all words of length '6' in the given sentence.
Example Output: four cute elttil ducklings swimming in the water

Example Input: Sentence: 'a black and white photo of people sitting on a bench'. Reverse all words of length '7' in the given sentence.
Example Output:
a black and white photo of people gnittis on a bench