用括号所给词的适当形式填空，使句子意思完整。The ground is covered with fallen (leaf) in autumn.
Many young trees (plant) in my country every year.
Students in our class have finished (read) the text.
I overslept this morning. By the time I got to the train station, the train (leave)
When the guest entered the hall, Mr. Smith stood up and greeted him (polite)