Mr Green is our English teach.We all like his lesson_課___because they are very Interesting有趣的____.He is from 來(lái)自____America.We are very surprised he likes making things 東西____.He sometimes有時(shí)____helps us make model planes or model cars.Today he gives us a smart robot.It can 能____do many thing for us.Look!It is cleaning 打掃_(dá)___ our classroom now.It is very easy for it to do this job 工作____.Perhaps it can clean the windows for us.I think it is dangerous 危險(xiǎn)的____ for people to do that.We often call our robot hardworking cleaner 清潔工____.