【正文】
Unit 6 When was it invented? listening amp。speaking Section A Period One “What’s this? ① ② ③ ④ It was made by Bell at first . 貝爾(人名) It used to be like this It is used for watching programs.(節(jié)目) [?pr??gr230。m] It was made of steel and iron [?a??n] 鐵 inventions [?n?ven?n]發(fā)明 When were they invented?