Modifiers matching obstruction:

• physical,
• lighted,
• underwater,
• permanent,
• immovable,
• vertical,
• solid,
• adjacent,
• hydraulic,
• insurmountable,
• short,
• environmental,
• significant,
• temporary,
• major,
• irregular,
• outdoor,
• hard,
• under,
• natural,
• nearby,
• horizontal,
• minor,
• fixed,
• topical,
• opaque,
• discrete,
• underground,
• electrical,
• relevant,
• visual,
• dense,
• overhead,
• artificial,
• featureless,
• internal,
• layer,
• subsurface,
• virtual,
• external,
• indoor,
• additional,
• cooler,
• past,
• linear,
• local,
• unusual,
• terrestrial,
• low,
• large,
• impenetrable,
• spatial,
• elongated,
• lateral,
• typical,
• mechanical,
• smaller,
• movable,
• raised,
• multiple,
• nasal,
• tall,
• rigid,
• larger,
• urethral,
• hazardous,
• structural,
• small,
• simple,
• clear,
• upright,
• over,
• taller,
• geographic,
• visible,
• common,
• metal,
• level,
• up,
• hidden,
• removable,
• surrounding,
• isolated,
• current,
• bigger,

Simple categories matching past:

• movement,
• event,
• success,
• activity,
• knowledge,
• war,
• works,
• attempt,
• emotion,
• happening,
• illness,
• instrument,
• experience,
• organization,
• thing,
• work,
• achievement,
• improvement,
• tradition,
• perception,
• dish,
• space,
• style,
• disturbance,
• competition,
• record,
• history,
• obstruction,
• bill,
• feeling,
• exchange,
• action,
• behavior,
• state,
• disaster,
• business,
• formation,
• content,
• situation,
• giant,
• sport,
• episode,
• society,
• week,
• training,
• disease,
• change,
• relationship,
• industry,
• hazard,
• civilisation,
• measure,
• practice,
• difficulty,
• catastrophe,
• problem,
• years,
• condition,
• inhabitant,