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 traffic light with road instructions directs traffic'. Reverse all words of length '4' in the given sentence.
Example Output: a traffic light htiw daor instructions directs traffic

Example Input: Sentence: 'two men are playing a wii boxing game'. Reverse all words of length '4' in the given sentence.
Example Output: two men are playing a wii boxing emag

Example Input: Sentence: 'a man water skiing with a life vest hanging on to a rope'. Reverse all words of length '1' in the given sentence.
Example Output:
a man water skiing with a life vest hanging on to a rope