two persons / a couple, pair

Irish person

the German people / a German person

a Spaniard

American person

an alien (life form of non-Earth origin) / Synonym of 宇宙飛行士 (uchū hikōshi, “astronaut”) (member of the crew of a spaceship or other spacecraft, or someone trained for that purpose)

workman / laborer / craftsman / artisan

extraterrestrial, alien

a Martian

a Venusian