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 man riding a bike down a street past cars'. Reverse all words of length '4' in the given sentence.

SOLUTION: a man riding a ekib nwod a street tsap srac

PROBLEM: Sentence: 'a couple of toothbrushes that are on a towel'. Reverse all words of length '6' in the given sentence.

SOLUTION: a elpuoc of toothbrushes that are on a towel

PROBLEM: Sentence: 'two animals eating something from the grass with a pretty flower bush'. Reverse all words of length '3' in the given sentence.

SOLUTION:
owt animals eating something from eht grass with a pretty flower bush