>She speaks several languages as DO her parents.
zamiast 'as do' mozna napisac 'and so do'. To jest taki sam przypadek inwersji jak w zdaniach typu "So have I", "neither can you".
I bought two tickets, as did my friend. (czyli razem 4 bilety)
>She runs her business exactly as her two brothers DO.
A tutaj "as" wiąże się z exactly