In this task, you need to remove 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.

Example Input: Sentence: 'a zebra in a tall grassy field watching deer in the background'. Remove all words of length '2' in the given sentence.
Example Output: a zebra a tall grassy field watching deer the background

Example Input: Sentence: 'a woman standing next a window in a living room looking at a box on the floor'. Remove all words of length '6' in the given sentence.
Example Output: a woman standing next a in a room looking at a box on the floor

Example Input: Sentence: 'a qantas spirit of australia airplane flying in a clear blue sky'. Remove all words of length '6' in the given sentence.
Example Output:
a of australia airplane in a clear blue sky