[['series 1', 'series 2', 'series 3', 'series 5', 'series 9', 'series 11'], ['peter jones', 'peter jones', 'peter jones', 'peter jones', 'peter jones', 'peter jones'], ['simon woodroffe', 'theo paphitis', 'theo paphitis', 'theo paphitis', 'theo paphitis', 'piers linney'], ['doug richards', 'doug richards', 'deborah meaden', 'deborah meaden', 'deborah meaden', 'deborah meaden'], ['duncan bannatyne', 'duncan bannatyne', 'duncan bannatyne', 'duncan bannatyne', 'duncan bannatyne', 'duncan bannatyne'], ['rachel elnaugh', 'rachel elnaugh', 'richard farleigh', 'james caan', 'hilary devey', 'kelly hoppen']]
Peter Jones and Duncan Bannatyne are the only 2 people who appeared consistently in all Series of dragon Den (uk)
[ENT] and [ENT] are the only [ENT] people who appeared consistently in all [ENT] of dragon [ENT]