补全对话（共5小题；每小题1分，满分5分）
A：Today we are going to talk about a great invention．It looks like a human being． 小题1:                 
B：It’s a robot．小题2: 
A：Of course not．The first robot was invented in 1921．
B：小题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： 小题4:
A：No．Robots can do a lot of work instead of people in many ways，but people wouldn’t be replaced by robots． 小题5:               
B：  We get it．

A．Is that clear? B．Can it do some washing? C．Why do you think it is useful? D．It appeared several centuries ago，didn’t it? E．Will robots be the same as people? F．What is it? G．Could you please tell me more about robots?