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: 'black and silver fire hydrant sitting next to a road'. Reverse all words of length '7' in the given sentence.
black and silver fire tnardyh gnittis next to a road

Sentence: 'a man skateboards in a park for skateboarding'. Reverse all words of length '2' in the given sentence.
a man skateboards ni a park for skateboarding

Sentence: 'a clock and a flag on a concrete building'. Reverse all words of length '3' in the given sentence.

a clock dna a flag on a concrete building