Answer:
gatekeeper
Step-by-step explanation:
The gatekeeper, teacher is learned with the responsibility of always determining who will talk, when and for how long, as well as the basic direction.
They are in-charge of ensuring that there is sanity, order and decorioum in any class setting. They do this by controlling the noise and the level at which discussion takes place.
They determine who talks and when the person should talk, also handles how long anyone should talk.
There role cannot be over-emphasised at all.