without   protect   goal   harmful make   warn   quick   nervous   when   danger

   

When people hear the word stress，they usually think of something bad．However，stress can have several benefits（益处）for the body and mind．To begin with，people may feel stressed（51） 　 　there is something important to do．For example，some students are stressed before a big test．The stress might make them feel （52） 　 　，but it also makes them focused．This type of stress can help people work efficiently（高效地）to meet their （53） 　 　．

Another way stress benefits us is by keeping us healthy．Scientists who study stress learnt a little stress can （54） 　 　the immune system（免疫系统）stronger．When your body learns to respond （反应）to some stress，it's able to （55） 　 　you better from illness．

The final way that stress benefits us is by helping us respond to （56） 　 　．If you see a car coming around the corner too fast，you might experience stress．This stress sends a message （57） 　 　your brain of danger，allowing your body to respond （58） 　 　．You may not be able to jump out of the car's way soon enough

（59） 　 　the stress．

Of course，too much stress is （60） 　 　to our bodies and minds．But the right amount of stress makes us more efficient，healthier and safer．