gradeeight是什么意思

　　例句：

　　Wang Zixuan, a student from Grade Eight, with little knowledge of painting, painted a beautiful night scenery on a piece of pottery.

　　王子轩是一个八年级的学生，他几乎不了解绘画知识，但却在一块陶器上画了一幅美丽的夜景。

　　I am a student in Grade Eight.

　　我是八年级学生。

　　I teach grade seven and grade eight 's biology now.

　　现在，我教七年级和八年级的生物。