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: 'a group of people loading a tour bus'. Reverse all words of length '3' in the given sentence.
a group of people loading a tour sub

Sentence: 'yachts are all tied up in a marina dock'. Reverse all words of length '3' in the given sentence.
yachts era lla tied up in a marina dock

Sentence: 'a person brushing their hair with a zac efron brush'. Reverse all words of length '8' in the given sentence.

a person gnihsurb their hair with a zac efron brush