I’m from Orange County, California, where I had the pleasure and honor of serving as a Newport Beach ocean lifeguard(救生员). Whenever I could, I got shifts(轮流/轮值) working the Point. The Point was known for its great rip currents(退流潮). Now and then it could be very dangerous.

So, late in a shift, I was working Tower 15. Two streets to my right was another guard named Mike, working Tower 17. He called me, “Hey, I got a couple of kids. I gotta   go and give them a warning. Keep an eye on us.” I said, “Sure.”

And sure enough, as soon as he hung up the phone, a rip current was coming up quickly under these two kids, and they were getting drawn out. All I saw was two small noses moving up and down in the water. They were in great danger. Mike was rushing quickly toward the sea.

By now, the mother of the two kids realized what was happening. She was crying crazily. I was also very worried and started running toward her, but before I was even halfway there, Mike reached the kids.

Mike swam sideways out of the rip current into the clear water and started bringing them in. When I reached their mother, Mike was in waist-deep water. The kids were so tired and afraid that they could not swim back by themselves, so Mike was carrying them, one under each arm.

I turned to their mom, “Hey, it’s OK. They’re safe.” I saw her stop crying and slowly start to calm down.

She turned back and got her first good look at Mike. He had a number of really terrible tattoos(纹身) on his strong arms and back, and his head showed the long scars(伤疤) he got from a broken beer bottle. Then a crazy thing happened. I saw a new kind of panic(惊慌) wash over her as though there was some new dangerous thing would happen to take away her kids’ lives. She rushed up to Mike, immediately caught her kids and walked away. Not even a thank-you.

Mike just looked at me and his tattoos on the arms, made a face, and ran back to his tower. I watched him with respect and came back to guard my own tower.

If any other guard had worked 17 that night, including me, there would be a very real chance that that mother wasn’t going home with both her kids.

Footprint means the influence that a person’s or organization’s activities have on the environment. Simply understanding it is very useful to us. (Let’s take the example of Mr. Brown’s footprints.)

Water is the source of life. We use water directly for drinking, cooking and washing, but we also use water indirectly for producing things such as food, paper and cloth. A water footprint tells us how much water is being used. It can help us come up with ways to save water. You can learn about how your daily habits influence your water use through the food you eat, the things you buy and even the energy you use.

(Chart I)                                                                                  (Chart Ⅱ)

A carbon footprint is the total amount of CO₂ a person or organization produces. We can use it to understand the influence of personal behavior on global warming (全球变暖). Most people are surprised when they see how much CO₂ their activities create. Then they begin to think about changing their daily habits to reduce(减少) their carbon footprints. For example, they can walk instead of using a car.

When you are at home, don’t leave the water or lights on when you don’t need it.

Meatless Monday is popular with people who want to eat less meat. The production of meat uses lots of energy and produces lots of CO₂.

The more we buy, the more we throw away later. Before you buy something, think about whether you really need it.

Everyone plays a role in making a greener Earth. If you know about your footprints well, you can think up more ways to protect the environment.