Modifiers matching invalid:

• innocent,
• crippled,
• insightful,
• optimistic,
• brilliant,
• weak,
• socially-unaware,
• socially-unintelligent,
• inspirational,
• scientific,
• inspiring,
• arrogant,
• socially-awkward,
• rigid,
• good-hearted,
• bumbling,
• kind-hearted,
• aloof,
• sympathetic,
• gentle,
• stubborn,
• gangly,

Simple categories matching rigid:

• block,
• fibre,
• robot,
• person,
• instrument,
• representation,
• hero,
• connection,
• tyrant,
• instrumentation,
• luggage,
• android,
• thermoplastic,
• form,
• container,
• sheet,
• part,
• unit,
• piece,
• shaft,
• appliance,
• bottle,
• solid,
• soldier,
• tissue,
• captain,
• detective,
• foam,
• scientist,
• means,
• tool,
• wall,
• sailor,
• foundation,
• object,
• implement,
• particle,
• gel,
• organs,
• panel,
• obstruction,
• architecture,
• item,
• support,
• fixture,
• case,
• textile,
• deposit,
• matrix,
• profile,
• fastener,
• class,
• article,
• alteration,
• tube,
• display,
• metal,
• change,
• adhesive,
• web,
• deck,
• barrier,
• splint,
• finish,
• cover,
• resin,
• aggregate,
• post,
• frame,
• thread,
• sector,
• floor,
• plastic,
• entity,
• body,
• transparency,
• hitch,
• organ,
• tubing,
• cloth,
• plant,
• polymer,
• sorbent,
• component,
• devices,
• medium,
• airfoil,
• monomer,
• mineral,
• element,
• lining,
• connector,
• packing,
• measure,
• structure,
• boundary,
• vehicle,
• feature,
• construction,
• cement,
• tip,
• filler,
• material,
• appendage,
• cutoff,
• molecule,
• stick,
• invalid,
• matter,
• sphere,
• macromolecule,
• space,
• layer,
• armour,
• protein,
• rod,
• rock,
• surface,
• cylinder,
• system,
• substrate,
• insulation,
• substance,
• fixing,
• base,
• fiber,
• paper,
• package,
• carrier,
• linguist,
• shape,
• covering,
• group,
• motion,
• member,
• movement,
• ground,
• coil,
• boot,
• fabric,
• casing,
• dictator,
• dressing,
• product,
• pavement,
• transformation,
• obstacle,
• device,
• document,
• sidekick,
• pipe,
• watercraft,
• hanger,
• mechanism,
• bed,
• plate,
• strip,
• portion,
• food,