New, former, great before the noun: tân, cựu, đại

In everyday Vietnamese a describing word follows the noun: tổng thống mới, the new president. A few Sino-Vietnamese ones go in front instead, and they're common in the news: tân (new), cựu (former), đại (great, big). Tân tổng thống is the new president; cựu học sinh are former students of a school; đại dịch is a pandemic, literally a great epidemic.

They attach to Sino-Vietnamese nouns, mostly roles and titles, and the pair becomes a fixed term: tân sinh viên (first-year students), tân binh (recruits, rookies), cựu chiến binh (veterans), đại dự án (mega-project). They don't go with everyday native words: a new house is nhà mới, never tân nhà.

For former officials, Vietnamese papers usually write nguyên, also in front: nguyên Bộ trưởng, the former minister. Cựu is common for alumni, veterans, athletes and foreign leaders.

In speech you'll hear these as fixed words: students talk about tân sinh viên, families about cựu chiến binh. For anything else, put the native word after the noun: giám đốc mới (the new director), giám đốc cũ (the former director).