已知直线l和两个不同的平面α，β，则下列命题中错误的是______ （请写出错误命题的序号）．

①若l∥α，l∥β，则α∥β

②若l⊥α，l⊥β，则α∥β

③若l⊥α，α⊥β，则l∥β

④若l∥α，α⊥β，则l⊥β

He speaks English well indeed,but of course not ______ a native speaker.[ ]

A. as fluent as  

B. more fluent than

C. so fluently as  

D. much fluently than