like: tầng trệt → →
das Erdgeschoss ☊ 
tầng trệt ☊ 
☊ das Erdgeschoss ☊ tầng trệt ☊ ☊ Sie verteilten sich im ganzen Haus, im Wohnzimmer, im Erdgeschoss, überall. ☊ Họ chạy toán loạn ở trong nhà, ở phòng khách, ở tầng trệt, khắp mọi nơi. ☊ (Lektion 32, Nr. 428) All the ground floor windows were fitted with bars. ☊ bar ☊
a ground-floor flat ☊ flat ☊
Most of the monkeys' food is found at ground level. ☊ ground ☊
My office is at street level (= on the ground floor). ☊ street ☊