（1）Mobile phones have developed quickly and

.
（2）If you look at your phone in

before sleep，it will do harm to your eyes.
（3）Here are

to protect your eyes if you don't want to give up using the phone.
（4）You should hold the phone

30 centimeters away from your face to protect your eyes.
（5）You can look at things 5 meters away from you and then

the tip of your nose.