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 bear in a field next to a pond'. Reverse all words of length '5' in the given sentence.
Example Output: a bear in a dleif next to a pond

Example Input: Sentence: 'there are two men sitting on a park bench'. Reverse all words of length '5' in the given sentence.
Example Output: ereht are two men sitting on a park hcneb

Example Input: Sentence: 'people on a mountain snowboarding in a group'. Reverse all words of length '12' in the given sentence.
Example Output:
people on a mountain gnidraobwons in a group