Destructive behavior

Has your cat started scratching or chewing furniture?

This covers behaviors like scratching sofas or carpets, chewing fabric or clothing, gnawing on cords, or chewing houseplants — anything that damages household items. **Cats aren't doing this out of "revenge" or to "cause trouble"** — almost all of this is normal instinctive cat behavior that just happens to damage human belongings.

Possible medical causes

If a cat chews non-food items along with other abnormalities, ask a vet to evaluate for pica-related nutritional or GI issues
Oral disease (tooth pain) can sometimes change a cat's chewing habits

Possible behavioral causes

Scratching: an instinctive need to sharpen claws, leave scent as territory marking, shed old claw sheaths, and it's also a display of confidence
Fabric chewing/sucking: less common, possibly seeking comfort; frequently seen in kittens and usually fades, though some breeds tend to keep it for life
Chewing houseplants: indoor cats lack access to grass, and this comes from exploratory curiosity or a desire for plant fiber

Warning signs — see a vet right away

Vomiting or decreased appetite after swallowing a cord, fabric, plastic, or other foreign object (suspected GI obstruction — an emergency)
Chewing on toxic plants (such as lilies, poinsettias, or ivy)
Destructive behavior suddenly increases dramatically with no identifiable environmental cause, combined with other abnormal symptoms

Initial at-home suggestions

Never use physical punishment or shout — cats can't learn "scratching the sofa is wrong"; they only learn "you appearing = danger"
For furniture scratching: observe the preferred material and orientation, and provide a matching scratching post right next to the spot it likes to scratch
For fabric/cord chewing: manage the environment (cord protectors) and provide alternative chew items
For chewing houseplants: first check whether any plants at home are toxic to cats (lilies are highly toxic to cats)
Trimming nails or using nail caps can reduce the severity of scratching damage

Sources: Cornell Feline Health Center. For reference only — please consult a vet.