Usage note
事先意思是做事情之前先准备好。
Shì xiān yìsi shì zuò shìqing zhīqián xiān zhǔnbèi hǎo.
In advance means to prepare before doing something.
Context note
事先常用于提醒别人提前计划，比如事先通知或事先准备。
Shì xiān cháng yòng yú tíxǐng biérén tíqián jìhuà, bǐrú shì xiān tōngzhī huò shì xiān zhǔnbèi.
In advance is often used to remind others to plan ahead, like notify in advance or prepare in advance.
5 examples
我们事先准备好了食物。
wǒ men shì xiān zhǔn bèi hǎo le shí wù。
We prepared food in advance.
她事先告诉我今天有考试。
tā shì xiān gào sù wǒ jīn tiān yǒu kǎo shì。
She told me in advance that there is a test today.
请事先打电话预约。
qǐng shì xiān dǎ diàn huà yù yuē。
Please call in advance to make a reservation.
他事先学习了课文。
tā shì xiān xué xí le kè wén。
He studied the lesson in advance.
我们事先商量了计划。
wǒ men shì xiān shāng liáng le jì huà。
We discussed the plan in advance.
5 mini stories
小文事先准备了雨伞。下雨时他没有淋湿。
xiǎo wén shì xiān zhǔn bèi le yǔ sǎn。 xià yǔ shí tā méi yǒu lín shī。
Xiao Wen prepared an umbrella in advance. He didn't get wet when it rained.
小华事先复习了功课。考试时他答得很好。
xiǎo huá shì xiān fù xí le gōng kè。 kǎo shì shí tā dá dé hěn hǎo。
Xiao Hua reviewed his lessons in advance. He answered well during the test.
小丽事先买了礼物。朋友的生日她很高兴。
xiǎo lì shì xiān mǎi le lǐ wù。 péng yǒu de shēng rì tā hěn gāo xìng。
Xiao Li bought a gift in advance. She was very happy on her friend's birthday.
小刚事先查了地图。他去公园没有迷路。
xiǎo gāng shì xiān chá le dì tú。 tā qù gōng yuán méi yǒu mí lù。
Xiao Gang checked the map in advance. He didn't get lost going to the park.
小美事先准备了水。去爬山时她不会渴。
xiǎo měi shì xiān zhǔn bèi le shuǐ。 qù pá shān shí tā bú huì kě。
Xiao Mei prepared water in advance. She won't be thirsty when climbing the mountain.
Mini dialogue
准备活动
A
我们事先需要准备哪些材料？
Wǒmen shìxiān xūyào zhǔnbèi nǎxiē cáiliào?
What materials do we need to prepare in advance?
B
事先准备好画笔和纸就可以了。
Shìxiān zhǔnbèi hǎo huàbǐ hé zhǐ jiù kěyǐ le.
Just prepare the brushes and paper in advance.
事先通知
A
老师事先通知了明天的考试。
Lǎoshī shìxiān tōngzhī le míngtiān de kǎoshì.
The teacher notified us about tomorrow's exam in advance.
B
那我们事先复习一下吧。
Nà wǒmen shìxiān fùxí yīxià ba.
Then let's review in advance.
Related words and contrasts
similar
提前
tí qián
ahead of time
Used when doing something earlier than planned.
similar
预先
yù xiān
beforehand
Often used in formal contexts.
opposite
事后
shì hòu
afterwards
Refers to after an event.