Hard or taught
Secure Steady Stable Strong Sturdy Strict
A synonym for changable is adaptable.
A synonym for common noun is word.
A synonym for debris is garbage. An antonym for debris is cleanliness.
detector or metal detectors
yes.
determined, fixed, rigid, set, firm
firm, steady, unbendable, unfaltering, unshakable, unwavering, staunch, unswerving
firm, solid, stiff, tough, durable etc
Some synonyms for 'enterprise' are business, venture, firm, initiative, or undertaking.
business, company, office, firm, department, organization, enterprise, establishment
Secure Steady Stable Strong Sturdy Strict
His determination, focus, and unyielding work ethic contributed to his success. The word unyielding is an adjective. The word firm is a synonym.
determined, fixed, firm, strong, immovable, inflexible, stubborn, unwavering, headstrong.
resolute, firm, dogged, intent, persistent, persevering, single-minded, tenacious
business, firm, association, corporation, partnership, establishment, syndicate, house, group, fellowship
If you mean hard as in the opposite of soft, then rigid, firm, adamatine. If you mean the opposite of easy, then difficult