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 is in the air riding a skateboard outside'. Reverse all words of length '2' in the given sentence.
Example Output: a man si ni the air riding a skateboard outside

Example Input: Sentence: 'a plate with a very big pile of cake with candles'. Reverse all words of length '4' in the given sentence.
Example Output: a plate htiw a yrev big elip of ekac htiw candles

Example Input: Sentence: 'a young girl cutting a piece of birthday cake with her parent'. Reverse all words of length '3' in the given sentence.
Example Output:
a young girl cutting a piece of birthday cake with reh parent