Before a noun or adverbial phrase, bothBfrombandBtobare acceptable in British English. 若用在名词或状语短语前，英式英语使用。
That's is incorrect. The subject is still "they". "in doing so" is just an adverbial phrase here. 现代信息系统更细微但却同样重要。它影响...
`Very quickly indeed' is an adverbial phrase. very quickly indeed 是状语短语。
Suject : Evolution of the web industry Verb: leads Object: developers Adverbial phrase: through sophisticated technologies waving .. server-oriented approaches (modifies "technologies") WEB工业的进展引导开发人员通过纵错复杂的技术，这技术在用户为主和服务为主两 个方法间波动求平衡。