简单机械 Simple Machines (16.06.21)

所有简单的机器都有助于使工作_________。

All simple machines help make work _________.

• 艰难 harder

• 容易 easier

哪个是滑轮的例子？

Which of the following is an example of a pully?

• 
• 

哪个是杠杆的例子？

Which of the following is an example of a lever?

• 
• 

哪个是螺旋的例子？

Which of the following is an example of a screw?

• 
• 

哪个是尖劈的例子？

Which of the following is an example of a wedge?

• 
• 

哪个是轮轴的例子？

Which of the following is an example of a wheel and axle?

• 
• 

哪个是斜面的例子？

Which of the following is an example of a inclined plane?

• 
• 

以下哪个可以使我们的工作更轻松？

Which of the following can make our work easier?

• 
• 

以下哪个可以使我们的工作更轻松？

Which of the following can make our work easier?

• 
• 

以下哪个可以使我们的工作更轻松？

Which of the following can make our work easier?

• 
•