When do people use a chart? 人们什么时候使用图表？

　　They use a chart when they show and sort data or information. 人们展示、分类数据或信息时会使用到图表。

　　A chart usually has numbers, symbols and other data. 图表通常包含数字、符号和其他数据。

　　Charts are very useful and they are also very helpful. 图表非常有用，对人很有帮助。

　　Charts should be easy, so everybody can read them more quickly. 为了让所有人很快看懂，图表要做得简单易懂。

　　There are many different kinds of charts. 图表有许多不同的种类。

　　They are a bar chart, a line chart, a pie chart, a tree chart and others. 可分为条形图、线形图、饼形图和树形图等等。