Ø 引用权威
1) …, wrote Edison, a great inventor.
2) Many years ago, a writer remarked that…
3) As one scientist wrote, …
4) A noted teacher once told me…
5) Many researchers find that…
Ø 深入阐述
1) But that’s only part of the story
2) Another equally important aspect is
3) Closely connected with this is
4) … may further be supported by
5) … is but one of many effects. Another is
6) So does…
7) Not only…but also…
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