Phone AMPLIFIER

i cant think about something to say.

a pen, a plastic cup, a tea box, duct tape, a wooden skewer and an utility knife.

mark two places: the place for the phone, and the place for the cup.

cut the places you marked.

cut the bottom of the plastic cup.

put the cup in the hole.

put the skewer in his place, reinforce the cup with duct tape, and your done.