2019学年度人教版选修八Unit3Inventors and inventions Period1Reading 课件(72张)
2019学年度人教版选修八Unit3Inventors and inventions Period1Reading 课件(72张)第2页

 Do you know the stages every inventor must go through before they can have their invention approved? Here give you some similar stages used in research, please out them in the suitable order.

Pre-reading