Modifiers matching ground:

• soft,
• hazardous,
• shiny,
• neutral,
• uncultivated,
• safe,
• coarse,
• old,
• high,
• rough,
• sandy,
• hard,
• holy,
• uneven,
• porous,
• disturbed,
• harder,
• low,
• open,
• clear,
• working,
• rocky,
• permeable,
• off,
• vertical,
• sized,
• clean,
• unsecured,
• waterlogged,
• routine,
• level,
• wet,
• loose,
• flat,
• stable,
• familiar,
• convenient,
• dry,
• electrical,
• paved,
• common,
• white,
• higher,
• metallic,
• grown,
• natural,
• firm,
• rigid,
• unstable,
• undisturbed,
• artificial,
• moist,
• new,
• dangerous,
• up,
• barren,
• sensitive,
• over,
• weak,
• under,
• sacred,
• difficult,
• slippery,
• metal,
• heavy,
• woven,
• elevated,
• durable,
• particular,
• mechanical,
• softer,
• private,
• conductive,
• good,
• bad,
• technical,
• irregular,

Simple categories matching flat:

• plate,
• component,
• surface,
• object,
• furniture,
• item,
• strip,
• mirror,
• equipment,
• ride,
• representation,
• artifact,
• charge,
• material,
• article,
• embellishment,
• condition,
• fabric,
• fish,
• textile,
• specimen,
• substrate,
• web,
• area,
• marker,
• string,
• bread,
• sign,
• solid,
• piece,
• ground,
• system,
• portion,
• ribbon,
• land,
• blank,
• tableware,
• plan,
• block,
• tool,
• topology,
• artwork,
• thing,
• section,
• underside,
• implement,
• original,
• brush,
• stage,
• substance,
• particle,
• paint,
• art,
• segment,
• design,
• slab,
• copy,
• food,
• device,
• floor,
• vehicle,
• work,
• flower,
• display,
• dish,
• content,
• course,
• structure,
• tissue,
• package,
• crystal,
• form,
• rod,
• waveform,
• board,
• bottom,
• plane,
• x-ray,
• shape,
• subject,
• lighting,
• drawing,
• conductor,
• side,
• member,
• ornament,
• roof,
• epithelium,
• part,
• book,
• abstraction,
• ceiling,
• region,
• image,
• cloth,
• weapon,
• foot,
• works,
• record,
• speaker,
• polygon,
• clothing,
• circuit,
• screen,
• base,
• medium,
• place,
• background,
• stick,
• painting,
• blade,
• creature,
• facility,
• paper,
• ware,
• wire,
• space,
• body,
• earth,
• wall,
• linen,
• feature,
• cookware,
• graphic,
• tin,
• metal,
• deck,
• cover,
• figure,
• gasket,
• rock,
• footwear,
• container,
• option,
• card,
• muscle,
• upland,
• instrument,
• document,
• road,
• tray,
• sheet,
• pad,
• bottle,
• terrain,
• support,
• mineral,
• product,
• panel,
• shield,
• stone,
• mold,
• fee,
• accessory,
• seal,
• tube,
• collection,
• glass,
• fruit,
• pan,
• foliage,