题目内容：

根据句意及提示写单词。

1.The train moved at high _____________(速度).

2. How to protect the ________________（环境）has been under discussion.

3. A sparrow was ______________(死). Let’s bury(埋) it under the tree.

4.Last weekend, my father bought a __________(两件，几件事物) of beautiful key rings for me.

5.We all love Liu Qian’s ________________(魔术).