The tense in Japanese is different from English.

He calls himself a professional guitarist.

He is a self-styled professional guitarist.

He is studying computer science at a specialized school.

There are many different specialty stores in this town.

He is a specialist fool, with no interest in anything outside his field.

He couldn't say anything about issues outside of his field of expertise.

He has expert knowledge.

He lost everything.

She is planning a date with her current boyfriend.