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 dog lays next to a bag on a couch'. Reverse all words of length '4' in the given sentence.
answer:
a dog syal txen to a bag on a couch


question:
Sentence: 'a guy on  a surf board by a very big wave'. Reverse all words of length '3' in the given sentence.
answer:
a yug on a surf board by a very gib wave


question:
Sentence: 'a man standing alone using a cell phone'. Reverse all words of length '1' in the given sentence.
answer:

a man standing alone using a cell phone