The teachers are engaging and entertaining, and the class materials, which you can download for personal use, are top-notch.

老师们很投入而且很有趣，可以下载供个人使用的顶尖课程材料。

Use pictures Pay attention to diagrams and graphs in your class materials, says Nebel.

7. 使用图片 注意课堂材料中的图表，内贝尔说。

It's taking class material and " asking a lot of how and why questions about it, " Nebel says.

内贝尔说，它会获取课堂材料并“提出很多关于如何和为什么的问题”。