白开水用英语怎么说？

plain boiled water
放冷了还叫凉白开。

LS你那是热开水吧～

(plain) boiled water

白开水
plain boiled water

warm water or ice water

no need to translate the word 白 and 开

just need to tell people if you prefer cold or hot ones

personal translation, fyi only

drinking water