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: 'two birds standing and sticking their heads in muddy water'. Reverse all words of length '3' in the given sentence.
owt birds standing dna sticking their heads in muddy water

Sentence: 'a street pole with some signs sitting on top of it'. Reverse all words of length '6' in the given sentence.
a teerts pole with some signs sitting on top of it

Sentence: 'animals are grazing in the grass by a mountain'. Reverse all words of length '1' in the given sentence.

animals are grazing in the grass by a mountain