However , for many years , physicists thought that atoms and molecules always were much more likely to emit light spontaneously and that stimulated emission thus always would be much weaker.
【解析】這個句子中主句是physicists thought that ... and that ...用結構圖表示就是:
It appeared that Canada was once more falling in step with the trend toward smaller families that occurred through all we Western world since the time of the Industrial Revolution.
【解析】句子的分層結構是:It appeared that...that...結構圖就是這樣
1.It appeared that ...
可以發現
2.Canada was once more falling in step with the trend toward smaller families.
加拿大再一次陷入了往更小化家庭發展的趨勢。
3.that occurred through all the Western would since the time of Industrial Revolution
這種趨勢曾經在工業革命以來整個西方世界出現過。
【例3】
The history of clinical nutrition or the study of the relationship between health and how the body takes in and utilizes food substances , can be divided into four distinct eras : the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents.
【解析】
這個句子的分層結構是:The history of clinical clinical nutrition can be divided into four distinct eras:...when ..that ...that...and that...這個句子中or 后面的the study 為clinical nutrition 的同位語,可以先省略不看。