重点讲解:
1. date back to 追溯(到);开始(于);始造(或建)(于);
The community's links with Syria date back to biblical times.
这个团体与叙利亚的关系可以追溯到《圣经》时代 。
2. kill off 被全部杀死;被灭绝;
Their natural predators have been ki lled off.
它们的天敌被全部杀死 。
3. lead to 招致;致使;导致;
The new system may be more economic but will lead to a decline in programme quality.
新系统可能更合算,但是会降低程序质量 。
4. add to 添加;增加;
I have nothing to add to my earlier statement.
我对我早先说的话没有什么补充的 。