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: 'a tennis player is swinging at a tennis ball'. Reverse all words of length '2' in the given sentence.

SOLUTION: a tennis player si swinging ta a tennis ball

PROBLEM: Sentence: 'a river filled with lots of boats and surrounded by buildings'. Reverse all words of length '4' in the given sentence.

SOLUTION: a river filled htiw stol of boats and surrounded by buildings

PROBLEM: Sentence: 'a plate full of donuts sitting on a counter beside a pair of scissors'. Reverse all words of length '2' in the given sentence.

SOLUTION:
a plate full fo donuts sitting no a counter beside a pair fo scissors