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.

Sentence: 'a large red truck on a city street'. Reverse all words of length '4' in the given sentence.
a large red truck on a ytic street

Sentence: 'three clocks on a wall telling different times on it'. Reverse all words of length '1' in the given sentence.
three clocks on a wall telling different times on it

Sentence: 'a couple of cows standing in a field'. Reverse all words of length '6' in the given sentence.

a elpuoc of cows standing in a field