Terms for subject Informal containing pin down

English	Russian
pin down	застать на месте (на рабочем: ... he is impossible to pin down)
pin down as	определить тип (чего-л.: A beautiful city but also a little melancholy. The population was so mixed, it would be hard to pin it down as a hippie town, a tech town, a college town, an arts town, a retirement town, or something else. I've heard it once described as "a beautiful city with no soul" and that's probably the best way I can think of it. (Reddit) ART Vancouver)