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 man is crouched down by a big elephant'. Remove all words of length '3' in the given sentence.
Example Output: a is crouched down by a elephant

Example Input: Sentence: 'a giraffe is leaning over and eating some leaves'. Remove all words of length '4' in the given sentence.
Example Output: a giraffe is leaning and eating leaves

Example Input: Sentence: 'a wall with a painting of a large toaster and smaller toasters on it'. Remove all words of length '3' in the given sentence.
Example Output:
a wall with a painting of a large toaster smaller toasters on it