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 bird perched on a wood rail by itself'. Remove all words of length '7' in the given sentence.
Example Output: a bird on a wood rail by itself

Example Input: Sentence: 'a group of people at a table in a room'. Remove all words of length '6' in the given sentence.
Example Output: a group of at a table in a room

Example Input: Sentence: 'a sign advertising a festival on h street ne washington dc'. Remove all words of length '6' in the given sentence.
Example Output:
a sign advertising a festival on h ne washington dc