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 triangular grouping of jet planes flying in the sky'. Reverse all words of length '3' in the given sentence.
a triangular grouping of tej planes flying in eht yks

Sentence: 'some people sitting on some benches flowers and buildings'. Reverse all words of length '3' in the given sentence.
some people sitting on some benches flowers dna buildings

Sentence: 'a red and white jet is taking off and some buildings'. Reverse all words of length '2' in the given sentence.

a red and white jet si taking off and some buildings