● 要素一: 时间状语，它包含过去时间（in previous centuries）和现在时间（in twenty-first century）。

● 要素二：比较对象，此题比较对象是（quality of life）。

● 要素三: 比较级，通常为形容词+er形式，或者为more+形容词，此题比较级为better。

A wide variety of transportation means have dramatically increased people’s mobility in the world. Compared with wagons and rickshaws, fast transportation, such as automobiles and planes, can provide us with an unparalleled combination of speed and comfort, greatly reducing the time and effort required to reach the destination. Thanks to fast transportation, the geographical barriers have been torn down, people are able to travel on almost any terrain on the earth, whether it is a raging river, rocky mountain or even dense jungle.

现如今，网络和通信技术发展提高了人们获取信息和交流的便利度。网络和通信技术的发展改革了人们沟通和信息分享的方式，世界各地的人们可以利用网络和通信技术进行资源共享或信息沟通。人们可以浏览新闻、快速地进行异地交流、网上消费、休闲娱乐等。过去人们只能靠耗时的书信联系，亲朋好友很久都见不到一面。

Nowadays, the advancement of technology gives rise to a vareity of sophisticated devices which enable people to gain knowledge and information conveniently. The advent of network technology has revolutionized the way people communicate and information-sharing. No matter where friends are, they can be reached at any time via telephone lines or cyber signals. Besides, modern people can browse news, purchase things, exchange ideas, watch movies or videos, and play electronic games online. By contrast, in the past, humans can only contact others mainly by sending them letters, seldom did they meet each other.

医疗技术的发展大大减轻了患者的痛苦、挽救了大量患者的生命，无数患者的生活质量和人均寿命得到了显著的提高。过去很多地方医疗资源严重不足，条件差、设备少，很多患者得不到救治。

Medical techniques are becoming more sophisticated in the present age, which significantly alleviates the suffering of patients and saves lots of lives. Moreover, modern approaches have considerably extended sick persons’ lifespans and maximized their quality of life. By comparison, in the past time, there were insufficient medical resources, poor medical treatment and limited equipments in many areas, numerous patients died because of the lack of efficient treatment.