Simple Antonyms: New/ Used

The can is new.

The can is used.

The can can not be both new and used because once something is used it is no longer new.

Gradable Antonyms: Neutral/ Drive

The car is in neutral.

The car is in drive.

the car can also be in sport and park so it has multiple options.

Reverse: Readable/ Unreadable

Your hand writing it readable.

Your hand writing it unreadable.

It can only be either or because either ya can read it or ya cant there isn’t really an in-between.

Converse: Employer/ Employee

She is my employer.

I am her employee.

One simply cant exist without the other. So both go together but separate

Taxonomic: Cheddar/ Mozzarella

The cheddar cheese was spoiled.

The Mozzarella cheese had not melted.

Both cheeses are from a bigger category which is cheese in general.