参考词汇：be careful, on line, danger, call...for, go bad
How to keep safe?
As teenagers, we should always keep safety in mind. But how can we keep safe? Here are some of my suggestions.
First, we should be careful when we make friends, especially on line. Second, if we are in danger, we must call the police for help in time so that we can keep ourselves safe. Also,we ought to eat healthily and safely. Eating food that goes bad will do harm to our health. Last but not least, summer is coming, and we must remember it's dangerous to swim in the river.