the voluminous personal papers of thomas alva edison reveal that his inventions typically (did not spring to life in a flash of inspiration but evolved slowly) from previous works.
几个问题：
1、not but连接平行结构，括号中的句子（正确答案）连接的并非平行对称结构
2、evolve...from用法对吗？fficeffice" />

1.not....but ....要求完全是对称结构，not一般过去式but一般过去式才是完全对称。
2.evolve...from用法错误。fficeffice" />