托福听力如何得高分

　　6.Lecture in a science and technology class： the female professor is talking about that in the long long human history， inventions and innovations always happen in one of the two ways： intentionally and accidentally.

　　First， she quotes an example of intentional innovation： bi-focus glasses. Before the bi-focus glasses were invented， people had to carry two pairs of glasses sometimes and this was very inconvenient. Thus， bi-focus glasses were intentionally invented to solve this problem.

　　Second， she takes another example of accidental innovation： the discovery of X-ray. When people first encountered X-ray in the lab， they had no idea of what this discovery meant，orwhere to put this discovery into application.

　　问题是：

　　Using points and examples from the talk， explain the two ways of innovation presented by the professor.

　　点评：复合类题型的解题关键在于作笔记。然后结合笔记进行复述。