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 girl with a cast on her arm stands in a bathroom'. Reverse all words of length '3' in the given sentence.

SOLUTION: a girl with a cast on reh mra stands in a bathroom

PROBLEM: Sentence: 'the bicyclists race toward an old brick church'. Reverse all words of length '2' in the given sentence.

SOLUTION: the bicyclists race toward na old brick church

PROBLEM: Sentence: 'a group of boys running in a grassy area'. Reverse all words of length '5' in the given sentence.

SOLUTION:
a puorg of boys running in a grassy area