揭示课题并板书课题：请再做一遍！

Hello, class! What are you doing?

youdao

为了提高计算速度，我们今天来学习一些加减法的简便运算。（板书课题）

We're going to learn the tricks of additions and subtractions in this class.

youdao

为了提高计算速度，我们今天来学习一些加减法的简便运算。（板书课题）

We're going to learn the tricks of additions and subtractions in this class.

youdao