Dear Tom,
How is it going? Yesterday I take part in a tree planting activity organized by our school. As environmental problems become more and more serious, I realized the importance of planting trees. My schoolmates and I took a school bus to a small desert and planted a lot of trees there. Though tired, I think it was meaningful to make efforts to the protection of our environment. It is everyone's responsibility to protect the environment. In the future I will try to save resources around me and contribute to the the world's environment protection. I am looking forward to your reply.

Yours sincerely,
Li Ke