A tiger is a kind of catamount animal. It looks like a cat, but much bigger than a cat. A tiger is very ferocious and it eats mainly meat. It has yellow and black streaks all over its body and it looks very beautiful. Its tail is long and strong and it can hit its quarry dying.
Tigers live in the thick forests and small animals in the forests are tigers' food.
During the past years, many forests have been cut down and the living conditions of the tigers are becoming worse and worse. There are fewer tigers left in the world now. Tigers are the animals of the world, and they should have their own living spaces. We must do our best to protect the tigers and their living environment.
绿色对眼睛有好处,并不是指绿色本身对眼睛有什么好处,而是说远眺大自然的景物可缓解眼睛的疲劳状态。如果看33厘米以内的东西,即使是绿色的,对眼睛也没有益处。
每隔1小时休息一下双眼,不要持续操作。持续使用电脑时,要经常眨眨眼睛,防止眼睛干涩。眼睛距离35厘米大的屏幕不应少于60厘米,距离38厘米大的屏幕不应少于70厘米。屏幕应放在略低于视平线的位置。将屏幕的亮度与清晰度调整到适当水平,以眼睛感到舒适为准。要经常擦拭屏幕。屏幕过脏会使图像模糊,造成眼睛疲劳。
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