| 1 | You had better open your mouth to relieve the pressure on your eardrums. | |
| 2 | Your eardrum oscillates 440 times per second-- you hear this tone. | |
| 3 | Moreover. it also describes vibration of drumhead and spread of electromagnet wave. | |
| 4 | Microscope " hematic blister " , discover its are a crinkly limbs, devour tympanic tick. | |
| 5 | Things get more complicated behind the eardrum, in the airfilled middle-ear cavity. |