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.

Sentence: 'three cows graze on the food that sits just outside their pens'. Reverse all words of length '5' in the given sentence.
eerht cows ezarg on the food that sits just outside rieht pens

Sentence: 'three people in uniform are cutting a cake'. Reverse all words of length '4' in the given sentence.
three people in uniform are cutting a ekac

Sentence: 'a cupboard with its doors open exposing the dishes inside'. Reverse all words of length '3' in the given sentence.

a cupboard with sti doors open exposing eht dishes inside