instruction:
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.
question:
Sentence: 'a large long train on a steel track'. Reverse all words of length '2' in the given sentence.
answer:
a large long train no a steel track


question:
Sentence: 'a photo in an airport showing a backpack and a cell phone'. Reverse all words of length '8' in the given sentence.
answer:
a photo in an airport showing a kcapkcab and a cell phone


question:
Sentence: 'a little black bear running across some rocks'. Reverse all words of length '7' in the given sentence.
answer:

a little black bear gninnur across some rocks