TASK 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.
PROBLEM: Sentence: 'the dog looks up at the cat sitting on a stone'. Reverse all words of length '1' in the given sentence.

SOLUTION: the dog looks up at the cat sitting on a stone

PROBLEM: Sentence: 'two giraffes standing next to a fence trying to reach the grass'. Reverse all words of length '6' in the given sentence.

SOLUTION: two giraffes standing next to a fence gniyrt to reach the grass

PROBLEM: Sentence: 'round tray of donuts behind a glass door'. Reverse all words of length '1' in the given sentence.

SOLUTION:
round tray of donuts behind a glass door