Unit 6 When was it invented? Section A. Talk about the inventions( 发明 ). Which one do you think is the most helpful in our daily life? Lead in.
Section B Period 2 Who? When? How? Say something about potato chips. Retell The history of potato chips.
Unit 6 When was it invented? Section A (1a—1c). Talk about the inventions( 发明 ). Which one do you think is the most helpful in our daily life? Lead in.
