一、根据所给单词的中文及句意填空。
1. The train travels at a ______________(速度) of 200 kilometres an hour.
2. Failure(失败) is the mother of _________________(成功).
3. Lily was _______(不幸的) enough to break her leg on the first day of her holiday.
4. Many people in Harbin like______________(滑雪) in winter.
5. Overwork will do _____________(伤害) to your health.
6. His uncle decided to go _____________(到国外) for further study.