when you look into a mirror,your image is reflected back to you.
后半部分变成主动句:1.The mirror reflects your image back to you.(back做副词修辞谓语，to you做状语)
2.The mirror reflects back your image to you.(reflect back做动词短语)
3.The mirror reflcts back to you your ...
Why
did the difference between the "white bikes" of the 1960s and of
1999?参见北师大高中英语必修第三册第8单元(p38)。请问句子中的
of the 1960s 和
of 1999 是并列结构吧，后面一个介词
of 可以省略吗？
Whatever else people disagree upon in Europe today, they at least agree on one point: Europe is in the midst of a profound debate about its future.Whatever做连接代词充当介词upon的宾语吗，那么upon这里表示什么意思？
... will closely study the circumstances behind the tragedy.BBC双语把这里的crush翻译为“踩踏”，但是我查字典看到crush的动词是“压扁，压碎，镇压”，名词比较接近的只有“拥挤的人群”的意思，并没有“踩踏”的含义，而且就算取动词的...