You will be given a definition of a task first, then some input of the task.
You are given an English sentence with a blank, and you need to predict the missing word. After completing, the whole sentence should be gramatically correct and non-ambiguous.

three times did the bell ring with a dull heavy sound seeming to participate in the general sadness before the concierge appeared and peeped through the door which he opened just wide enough to allow his ____ to be heard
Output:
words