阅读材料，完成下列要求

    1916年爱因斯坦预测引力波的存在，在一百年后的今天，美国科学家于2016年2月11日宣布，“激光干涉引力波天文台（LIGO）”第一次直接探测到来自于两个洞合并的引力波信号，证实了爱因斯坦引力理论的最后一项预言，震动世界。引力波是加速中的质量在时空中所产生的波动，也被比喻为时空的“涟漪”。爱因斯坦的广义相对论认为，任何有质量的物体加速运动都会对周围的时空产生影响，其作用的形式就是引力 波，广义相对论的其他预言如光线的弯曲、水星近日点进动以及引力红移效应都已获证实，唯有引力波一直徘徊在科学家的“视线”之外。引力 波探测为人类开启了宇宙观测的全新窗口，将为我们揭示宇宙新的奥秘。

    LIGO的发现让我国科学家对中国引力波研究充满期待。中科院高能所研究员张新民认为，我们必须抓紧，创新而不是跟踪，希望借此机会更大推动国内引力波研究的发展，作出我们应有的贡献，中科院高能物理研究所所长王贻芳院士表示，由于国内引力波研究基础薄弱，所以“阿里实验计划”将通过国际合作来实施，引进国际团队，而我们也参与国际在南美的实验，以此快速提升我们自己的研究能力。

    Dear Adam,

    I'm on vacation in Central America and having a great time. I'm in Guatemala. It's a small country but there is so much to see and do! There are volcanoes (火山), mountains, rainforests, beaches and Mayan temples (玛雅寺庙) in the country.

    The Mayan people have a long and interesting history. They built many temples. Last Friday I visited a Mayan temple at a place called Tikal. The temple has a history of about 1,300 years. It is a wonderful place to visit.

    I am staying at Lake Atitlan now. Some people say it is the most beautiful lake in the world. It is a very big lake and there are mountains and volcanoes around it. You can walk around the lake and even climb to the top of a volcano.

    The volcanoes at Lake Atitlan are not active volcanoes (活火山), but tomorrow I am going to see an active volcano called Pacaya. Active volcanoes can be dangerous because they still erupt (爆发) sometimes. I want to climb Pacaya. It erupted in 2010. I hope it won't erupt when I' m there!

      I'll send (发送,) you another e-mail soon.

                                                      All the best,

                                                       Kate

①是中华文化一脉相承的重要见证

②能将大量的史实记载并传承下来

③是中华文化的基本载体，成果丰富

④是人类进入文明的标志，具有展示人民的精神世界的独特作用