从观察笔记到成稿：一张交通折线图的完整示范

下面是一张教学用折线图。它记录某城市 2010、2015、2020 年每天使用三种交通方式的人数（千人）：公交为 50、40、30；地铁为 45、65、80；自行车为 20、35、40。

先写观察笔记

不用造句，只留关系：公交持续下降；地铁持续上升并在 2015 年成为最高；自行车也增长，并在 2020 年超过公交。起点时公交与地铁接近，终点时地铁明显领先。

这些笔记已经决定了文章重心。Overview 写两种相反趋势和终点格局；第一组细节比较起点接近、方向相反的公交与地铁；第二组写自行车，并交代它何时超过公交。

一篇可能的成稿

The line graph compares the daily numbers of people using buses, the subway and bicycles in a city in 2010, 2015 and 2020.

Overall, subway use and cycling increased, whereas bus ridership declined throughout the period. By 2020, the subway was by far the most widely used mode, while bicycles had overtaken buses.

Buses and the subway started at similar levels, with 50,000 and 45,000 users respectively in 2010. Their figures then moved in opposite directions: bus use fell to 40,000 in 2015 and 30,000 in 2020, while subway use rose to 65,000 and then 80,000.

Cycling remained less common than the other two modes in 2010, at 20,000 users. However, the figure increased to 35,000 five years later and reached 40,000 in 2020, placing it 10,000 above bus use at the end of the period.

文中没有写图上的每一个潜在比较。选择公交和地铁，是因为它们起点接近而方向相反；单独交代自行车，是因为它从最低位增长到超过公交。fell、rose 和 overtaken 都能在给定数据中找到依据。

常见的四段形式在这个例子中很自然，但重点不是复制四段，而是让概述中的每个判断在细节里都有数据支撑，并确保成稿没有超出图表能证明的范围。