There are many deserts (沙漠) on the earth. And the following are some facts you may find interesting.

What are deserts like?

Deserts can be hot and dry places. Rain may not fall there for months or years. Some deserts are sandy and stony (多石的). Deserts can also be very windy places. The wind can change the shape of the deserts. It moves sand around from place to place.

Temperatures in the desert can vary enormously(非常). During the daytime, the temperature may reach 40℃ even in the shade (阴凉处). At night, deserts can become very cold. In winter there may even be a frost (霜冻) in the early morning.

Living in the desert

The camel is sometimes called "the ship of the desert". It stores food in its hump (驼峰) and can go for days without water. It has large feet which help it not to fall into the soft sand. Its long eyelashes (睫毛) keep out the sand during sandstorms.

An oasis is an area of the desert where water may be found. The water may be in pools or under the ground. People and animals visit an oasis for water and food. Plants grow at an oasis. Some farmers are able to grow crops here.

The Arabian Desert

The Arabian Desert lies between the Red Sea and the Arabian Gulf. In some parts of the desert, it is too hot for people to live. Oil was discovered under parts of the desert and in the Arabian Gulf. This oil has made some countries in the area very rich. Much of the money has been spent building fine cities with lovely parks and lakes, and people live a comfortable life there.

Every year, millions of birds are killed or hurt when they fly into buildings. Why does this happen?  Birds are flying into windows and tall buildings that are all covered by glass.

Many birds fly from one place to another. Most of the time, they live in the wild, such as forests and wetlands.  They might see small trees and flowers inside a window and want to rest on these plants. The birds do not know there is glass between them and the plants.  

Some birds fly at night. They use the moon and stars to help guide them in the right direction. Tall buildings with lights on at night can confuse（迷惑）the birds.  The birds see the light, but they cannot tell that the light is coming from inside a building. They fly toward the light and crash into a building. On many mornings, there might be several dead birds lying on the ground.

  Many office buildings now turn off their lights at night. This helps reduce the number of birds that fly into buildings and it also helps save energy.

People in the office usually sit for most of the day when they work. But this is bad for a person's health. When people sit for too long every day, they don't move very much. So it is easy to start getting fat. Sitting too long is also bad for their work because it makes them want to sleep. When this happens, people may make more mistakes in their work or spend more time finishing their work. Companies need workers to be healthy, so how do they fix the problem?

Some companies have different types of desks to help their workers. The first type of desk is the standing desk. The desk can be taller when a person wants to stand. It can also be shorter when the person wants to sit. Another type of desk is the walking desk. This desk is made so that a person can work while walking at the same time.

Workers in the companies like the different types of desks very much. They think these desks are quite useful.