阅读理解。 根据短文内容,判断句子的正误.正确的在括号内写“T”,错误的写“F”。 If you go into the forests with friends, stay with them. If you don't,you may get lost. If you do get lost, this is what you should do. Sit down and stay where you are. Don't try to find your friends. Let them find you. You can help them to find you by staying in one place. There is another way to help your friends or other people to find you. Give them a signal (信号) by shouting or whistling (吹口哨) three times. Stop. Then shout or whistle three times again. Any signal given three times is a call for help. Keep on shouting or whistling, always three times together. When people hear you, they will give two shouts or two whistles. When a signal is given twice, it is an answer to a call for help. If you don't think that you will get help before night comes, try to make a small room with branches (树枝). What should you do if you get hungry or need to drink water? You would have to leave your little branch room to look for something to eat and drink. Don't just walk away. Drop small branches as you walk so that you can find your way back. The most important thing to do when you are lost-stay in one place. (     )1. If you get lost in the forests, you should walk everywhere to find your friends as soon as possible. (     )2. You can keep on shouting or whistling always three times together for help. (     )3. When you hear two shouts or whistles, you know that people will come to help you. (     )4. You can't go anywhere even when you feel thirsty or hungry. (     )5. You can find your way back to your branch room easily without leaving any branches as you walk.