People are able to hear well，being able to hear high and low sounds through ears. People's ears have three different parts.
The outer ear is the part of the ear that people can see. The size and shape of people's ears is random（随机的） and it doesn't affect their hearing. People with big ears don't hear better than people with small ears!Some people choose to put earrings at the earlobe，the bottom of their ears，but this doesn't affect hearing. Even though this is the main part of the ear you can see，all it does is to collect sound and send it down into the middle car—a part like a satellite dish（蝶形卫星接受器） collecting a signal.
The outer ear ends where the eardrum（鼓膜） starts. The area after the eardrum is called the middle ear. The sound that enters the outer ear makes the car drum shake and the middle ear is the place where the sound gets louder.
The sound travels through the inner ear into something called the cochlea（耳蜗）. This part is filled with liquid（液体） and covered in tiny（细小的） hairs. As sound waves（声波） travel from the outer to the inner ear，they make waves in the liquid of the inner ear，which in turn moves the tiny hairs in the ear that send sound or movement signals to the brain（大脑）.
