閱讀理解
Besides calling 911, here is what to do in some life-threatening emergencies when no one is around to help．
Lost in the wilderness
First, you've got to acknowledge(承認)you're in trouble．Stay where you can be seen clearly and remember to rest．Keeping a sense of humor helps too－it reduces stress and helps creative thinking．In a wide open area, make a colorful cross out of rocks to show your present position．
Choking
Aim to hit the top of the chair against your stomach in the soft part below the bony upside-down V of the ribs(肋骨)．Make a sudden push against the chair．If you still can't breathe after six tries, call 911, even if you can't talk．Write the word choking somewhere nearby, and leave the line open until help arrives．
Severe bleeding
Use your hand or clean cotton, or paper towels, or a scarf, or any cloth you can find, and push down on the wound until the bleeding stops．But if you put a bandage around your leg tightly, you're going to close the vessels(血管)to the entire leg．In this way, you could lose your foot．
Bear attack
If you surprise a bear, don't run away．That invites an attack．Instead, stand up and back away slowly without looking the bear in the eyes．If it does charge at you, stick out your chest, raise your arms, and spread your legs．Shout at the bear to frighten it．If it’s going to attack, lie face down, with your hands held firmly behind your neck．Play dead until you’re sure the bear is gone．
