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 cat is playing with the bottom part of the umbrella'. Reverse all words of length '3' in the given sentence.

SOLUTION: a tac is playing with eht bottom part of eht umbrella

PROBLEM: Sentence: 'four boxes of pizza sitting on a table'. Reverse all words of length '2' in the given sentence.

SOLUTION:
four boxes fo pizza sitting no a table