题目内容：

 

A: Today we are going to talk about a great invention. It looks like a human being.  1.

B: It’s a robot.   2.

A: Of course not. The first robot was invented in 1921.

B:    3. .

A: Sure. They can take the place of humans to do some boring work. They can also do a lot of dangerous work instead of humans.

B: 4.

A: No. Robots can do a lot of work instead of people in many ways, but people wouldn’t be replaced by robots.  5.

B: We get it.