语法总结
not only ... but ... as well
not only 修饰 spoke English very carefully，but...as well 补充 clearly，构成递进并列。
相似句：
- She not only sings but dances as well.
- He not only reads but writes as well.
neither ... nor ...
spoke neither slowly nor clearly 表示两者都不，连接两个副词。
相似句：
- He is neither tired nor hungry.
- She can neither sing nor dance.