adverb🔗Share事先，预先 (with present-tense constructions) First; beforehand, in advance."Previously, I had planned to study for the math test on Saturday. "事先，我计划星期六复习数学考试。timepastlanguageessentialChat with AIVocabulary GamePractice Reading
adverb🔗Share以前，先前. (with past-tense constructions) At an earlier time."My mom had previously worked as a teacher, but now she's a librarian. "我妈妈以前当过老师，但现在她是一名图书管理员。timepastessentialChat with AIVocabulary GamePractice Reading
