用所给词的适当形式填空。

1. She ________(have) to study for her Chinese test on Wednesday.

2. Mr. White, I am ________ ( real) busy now.

3. Please give the ________ (invite) to her.

4. Li Weifeng has soccer ________ (train) every day.

5. Thanks a lot for________ ( sing) this beautiful song for us.

网络上对社会现状不满，急于改变现实的青年，统称为什么？