Definition: 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.
Input: Sentence: 'a desktop computer monitor sitting on top of a desk next to a red bottle of water'. Reverse all words of length '8' in the given sentence.

a desktop retupmoc monitor sitting on top of a desk next to a red bottle of water