Event/Time + 之前, Clause
之前 means "before" and is placed after a time expression or event to indicate what precedes it. It functions as a more formal alternative to 以前 and is used in both written and spoken Chinese. For example, 出发之前 means "before departing."
出发之前,请检查一下你的行李。
chūfā zhī qián, qǐng jiǎnchá yīxià nǐ de xínglǐ.
Before setting off, please check your luggage.
睡觉之前,他习惯看半小时的书。
shuìjiào zhī qián, tā xíguàn kàn bàn xiǎoshí de shū.
Before going to bed, he has a habit of reading for half an hour.
做决定之前,你应该多听听别人的意见。
zuò juédìng zhī qián, nǐ yīnggāi duō tīngtīng biérén de yìjiàn.
Before making a decision, you should listen more to other people's opinions.