【答案解析】
Today is a good day. All of my classmates and I went to Dashu Mountain to plant trees. We got to the foot of the mount at 8:30. We began climbing soon after. On our way the air was so fresh and the scenery was so beautiful. Everybody was chatting happily. We reached the top at about 10: 00. The long river appeared in the north, and over the river there was a great bridge. We felt very relaxed. After a few minutes" break, we started to plant trees. Everyone dug holes, moved young trees into the holes, and covered the holes with mud. We all worked hard. About 11:30, we finished and left. Though we were very tired, we felt very happy.