英语翻译
Scientists look at the world and try to desiribe and explain what they see.
To explain what they have seen,they build a theory about the way in which things happen and the causes and effects.
Finally,the scientists test the theory to see if it matches what they have seen and if it can predict future events.
People who listen to Hawking's lectures sometimes find it difficult to understand him,because his thoughts and ideas often seem as large as the universe he is trying to describe.