One possible version:
Dear Chris,
I'm happy to receive your email asking about what we are doing to promote a low-carbon lifestyle.Now let me tell you something about it.
A campaign with the theme of "Actions Make a Difference" is going on in our school to call for a low-carbon life.For means of transportation,we now take buses,ride bicycles or walk if we can.Besides,we choose to use e-cards instead of traditional greeting cards.We only print things out when necessary,and print double-sided.And we try to save water and electricity in our daily life.For example,we are encouraged to have a shower instead of a bath,which uses far less energy and water.We always remember to switch off all appliances and lights when we're not using them.
What about you?Looking forward to your reply.[来源:高.考.资.源.网]
Yours,
Li Hua