Thread: Был transforms the predicate to the instrumental case!

Originally Posted by it-ogo

Yes, this is a quirk. The verb "быть" (был-есть-будет) requires instrumental for its direct object in all forms but Present tence.

Быть врачом.
Он был врачом.
Он (есть) врач.
Он будет врачом.

I don't know why it is so.

It is only for "быть", for example, equivalent verb "являться" requires Instrumental in all forms including Present.

So in response why is the example I posted; Концерт вчера вечером был плохой! why is плохой not плохим? as we have the verb Был and a subject + participle.