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: 'a kitchen counter filled with various types of fruits and vegetables'. Reverse all words of length '4' in the given sentence.
Example Output: a kitchen counter filled htiw various types of fruits and vegetables

Example Input: Sentence: 'red traffic signal on an island in the middle of a wide street'. Reverse all words of length '4' in the given sentence.
Example Output:
red traffic signal on an island in the middle of a ediw street