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 child on bench sticking out her tongue'. Reverse all words of length '6' in the given sentence.
Example Output: a child on bench sticking out her eugnot

Example Input: Sentence: 'a male cow walking down a street with shanties'. Reverse all words of length '7' in the given sentence.
Example Output: a male cow gniklaw down a street with shanties

Example Input: Sentence: 'a mirror on a moped showing the reflection of a building in the background'. Reverse all words of length '8' in the given sentence.
Example Output:
a mirror on a moped showing the reflection of a gnidliub in the background