set frame

例句：

1. 1. We need to setthe table for dinner.
   我们需要为晚餐准备餐桌。
2. 2. The teacher set the students to workon their projects.
   老师让学生们开始做他们的项目。
3. 3. She set the timer andstarted the experiment.
   她设定了计时器，开始了实验。