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.

Input: Consider Input: Sentence: 'a mountain towers over a train going down the tracks'. Remove all words of length '4' in the given sentence.

Output: a mountain towers a train going the tracks


Input: Consider Input: Sentence: 'this amtrak train is making its way down the tracks'. Remove all words of length '4' in the given sentence.

Output: amtrak train is making its way the tracks


Input: Consider Input: Sentence: 'a batter ready to hit the ball with the catcher and umpire behind him'. Remove all words of length '6' in the given sentence.


Output: a ready to hit the ball with the catcher and him