Can you imagine a sea of sand three times bigger than India? This is the Sahara Desert , the largest desert in the world. It covers ll countries in North Africa and is over 9 million square kilometers. In the Sahara , temperatures are very different during the day and at night. It is much hotter during the day than at night. During the day , the hottest time is between 2 pm and 4 pm-when temperatures rise to 33C. But it is very cold at night , the coldest time is at 4 am , when temperatures fall to -1°C. Because of the extreme temperatures in the desert, it is a very difficult place to survive( 幸存 ).Marco Rivera, our survival expert, has some tips. Take warm clothes and a blanket. You will need a hat, long trousers and a thick sweater to keep you warm at night. During the day, cover your body, head and face. Clothes protect you from the sun and keep water in your body. You will also need a warm blanket at night. It can get cold rapidly. When the temperature drops, it can be a shock and make you feel even colder. Try to drink some water at least once every hour. You need your water to last as long as possible. Drink only what you need. If you eat, you will get thirsty and your water will run out soon. You can eat a little, but only to stop you from feeling very hungry. Eat a small amount of food slowly. It's important to stay out of the sun during the day. Make a hole under your car and lie there. This will keep you cool and help you sleep. Find a warm place to sleep at night. A small place near a tree or a rock will be the warmest, But be careful before you decide where to sleep. Dangerous animals like snakes also like to sleep in these places. Look carefully for animals before you lie down.