题目内容

Sunglasses can help your eyes in two important ways. They improve the normal light filtering abilities of your eyes and they protect against the sun's damaging rays. Good sun glasses will reduce strong light, filter out(滤除)99 to 100 percent of ultraviolet(UV)rays(紫外线) , provide visual protection, comfortable and not distort colors.
The UV rays in sunlight can damage your eyes, some of the damage can be immediate while some occurs over a life time of exposure.
Good quality sunglasses help to protect your eyes from harmful UV radiation. It is generally agreed that the less UV rays that get through, the better. Experts recommend that to protect your eyes from harmful rays, your sunglasses should block 99 to 100 percent of both UV-A and UV-B rays. Furthermore, lenses should block at least 70 percent of visible light but even this can vary with the situation. In areas where light is strong such as at the beach or on snow, as little as 10 to 15 percent of transmission is better.
Selecting the right sunglasses is an important choice to protect your eyes and your vision(视力) . When selecting sunglasses for children, keep the following suggestions in mind.
Check the sunglasses often to make sure they fit well and are not damaged. Children often don't tell about their vision even when there's a problem, so a regular check may be necessary.
Select sunglasses that suit children's active lifestyles. The glasses should be impact (冲撞) resistant, and the frames should be bendable, unbreakable. Children's sunglasses should never be made of glass, unless required by their eye doctors.
The lenses should be large enough to protect the eyes from most angles (above, below and either side) and to block light that gets in around the frames. The sunglasses should fit the child's nose, to reduce the amount of sunlight that enters the eyes.
Sunglasses can protect our eyes and be comfortable at the same time by______.

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