Ying Na says

I turn the wifi off when I go to sleep. I hate to do it but my friend Weng Yao inspired me to do so. This helps to save electricity.

Bill shouts

I take the bus. I am Bill. I take the bus only, because it is cheap and I can help save the earth by doing this.

Gordon says

Every night I turn off my fridge. The food always tastes funny but to save the world, I don't mind getting diarhea every night :-)

Weng Yao says

Walk Only. In the 17 years and 3 months of my existence, I have only walked. To my toilet, to my school, to my hometown Hong Kong. It's great!