Terahertz　(THz)　metamaterial　sensing,　an　emerging　technology　in　biomedical　sciences,　has　made　considerable　progress　with　unique　characteristics,　such　as　label-free,　non-invasive,　non-destructive,　and　efficient.　However,　excellent　sensing　performance　involves　the　need　for　extremely　strong　light-matter　interaction　that　is　difficult　to　implement　for　the　intrinsic　divergent　electric　field　excited　on　the　surface　of　metamaterials.　Here,　an　innovative　method　of　manipulating　the　electric　field　to　realize　maximumly　light-matter　interaction　for　enhancing　liquid　sensing　at　THz　frequencies　is　reported.　The　electric　field　of　electromagnetically　induced　transparency　(EIT)　resonance　is　tightly　confined　inside　the　structure　around　the　quasi-dark　mode　by　optimizing　the　fully-enclosed　metamaterial　structure　design.　More　importantly,　the　electric　field　is　enhanced　and　the　part　that　permeates　into　the　substrate　is　exploited,　together　with　the　formation　of　inartificial　fluid　loading　units　by　the　effective　regional　substrate　etching,　exhibiting　the　enhanced　interaction　between　the　polar　liquids　and　the　THz　waves.　The　measurements　reveal　a　significantly　improve　in　sensitivity　of　0.312　THz/RIU,　which　is　9.8　times　that　without　etching　by　contrast.　The　strong　light-matter　interaction　implements　in　THz　metamaterial　via　the　electric　field　manipulation　holds　bright　promises　for　realizing　highly　sensitive　THz　sensing,　forging　a　route　for　real-time　supervising　trace　biomolecules.