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 wooden bench sits on top of a grass hill'. Reverse all words of length '2' in the given sentence.
Example Output: a wooden bench sits no top fo a grass hill

Example Input: Sentence: 'man riding a skateboard at the top of a ramp while others watch'. Reverse all words of length '6' in the given sentence.
Example Output: man gnidir a skateboard at the top of a ramp while srehto watch

Example Input: Sentence: 'two men in yellow one trying on a very strange hat'. Reverse all words of length '4' in the given sentence.
Example Output:
two men in yellow one trying on a yrev strange hat