在一场精彩的英文辩论赛中，恰当的开场白不仅能够吸引听众的注意力，还能为整场辩论奠定基调。以下是一些常用的开场语句，供参赛者参考：

1. "Ladies and gentlemen, today we gather here to explore a topic that is both timely and significant."

2. "Good afternoon, esteemed judges and fellow debaters. We stand before you to present our perspective on this important issue."

3. "Imagine a world where [briefly describe the scenario]. This is the essence of what we will discuss today."

4. "History has shown us that [relevant historical fact or trend]. Let us delve into how this impacts our current debate."

5. "In the grand scheme of things, [introduce the main argument briefly]."

6. "Today, we ask ourselves: Is it possible to [pose a question related to the topic]?"

7. "As we embark on this discussion, let us consider the implications of [key concept or idea]."

8. "The crux of our argument lies in understanding [main point], which we believe is crucial for [relevance to the topic]."

这些开场语句可以根据具体辩论主题进行调整和润色，以确保它们与辩论的内容紧密相关。记住，一个好的开场不仅能赢得评委的好感，还能为后续的论述铺平道路。