kzbin.info/www/bejne/d4DMgnueabWIjck not "ласкаво просимо", it's incorrect. When a girl gives a pen, a guy takes the pen and says "дякую" (djakuyu). The girl can reply "прóшу" (próshu, stress on O like in Polish proszę) because it's a small thing and it costs nothing to her or "будь ласка" (bud' laska) or "нема за що" (nema za scho = not at all) if the girl made some effort, but definitely not "ласкаво просимо" because it's about to welcome the boy at new job place - ласкаво просимо до офісу, at home - ласкаво просимо, about asking to visit Ukraine - ласкаво просимо до України

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