Try HanyuGuide's novel active Spaced Repetition System.
Audio is licensed under Creative Commons Attribution-ShareAlike 4.0 International License, building on the work of CC-CEDICT.
Sign in to save this word to your study lists.
oxygen (chemistry)
first of the ten Heavenly Stems 十天干[shí tiān gān]
(bound form) base; foundation
alkoxy (chemistry)