Last weekend, I took part in a forest clean-up activity. It was organized by Green Hope, an organization devoted to protecting forests.起初，我不想参加，    1    but then I thought, “What if nobody goes?”

Our team leader, Joe, took us to a forest outside the city. I was sad to find rubbish everywhere.     2    There was a “No littering” sign at the entrance to the forest, but that didn’t stop people from throwing their rubbish on the ground. Joe divided us into two groups:    3     one group cleaned up the north side of the forest, and the other the south side. After several hours’ work,看到森林比以前看起来要干净些，我们很开心    4    It was absolutely worth our effort!

There will be another clean-up activity in the greenbelt next Saturday. You can call Joe and sign up    5     if you would like to help. Everyone who takes part in the activity will receive a medal. I’ll join you too if I have time.