Achieving　dynamic　switching　among　absorption　(A),　reflection　(R),　and　transmission　(T)　states　is　not　only　essential　for　advancing　the　understanding　of　light-metasurface　interactions　but　also　holds　significant　potential　for　practical　applications,　such　as　selective　electromagnetic　shielding　and　smart　windows.　However,　at　terahertz　and　higher　frequencies,　implementing　active　elements　in　multilayer　configurations　presents　challenges　that　are　not　as　straightforward　as　those　encountered　in　the　microwave　range.　In　this　work,　it　is　demonstrated　that　tristate　ART　tuning　can　be　realized　in　a　single-layer,　free-standing　metasurface　by　switching　between　a　dual　dipolar　mode　(electric　dipole　and　magnetic　dipole)　and　a　single　dipole　mode　(electric　dipole).　By　transferring　a　flexible　vanadium　dioxide　(VO2)　thin　film　onto　the　free-standing　dielectric　Huygens＇　metasurface,　ART　modulation　is　achieved,　transitioning　from　a　near-unity　transmission　state　to　a　near-perfect　absorption　state,　and　finally　to　a　high-reflection　state　with　the　reflection　up　to　0.65　during　the　insulator-to-metal　transition　induced　by　heating　onto　the　phase-change　material.　The　results　may　lead　to　new　approaches　in　designing　reconfigurable　metasurfaces　based　on　phase-change　materials　for　wavefront　control　and　electromagnetic　shielding　applications.