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 passenger train moves along tracks near a field and trees'. Reverse all words of length '1' in the given sentence.

SOLUTION: a passenger train moves along tracks near a field and trees

PROBLEM: Sentence: 'a large long train on a steel track'. Reverse all words of length '2' in the given sentence.

SOLUTION: a large long train no a steel track

PROBLEM: Sentence: 'the bear is standing and looking down at something that is in its hands'. Reverse all words of length '4' in the given sentence.

SOLUTION:
the raeb is standing and looking nwod at something taht is in its hands