Once bitten, twice shy.
2.壹言既出，駟馬難追
A word spoken is past recalling.
3.壹見鐘情
To fall in love at first sight.
4.壹箭雙雕/壹舉兩得
Kill two birds with one stone.
5.壹寸光陰壹寸金
Time is money.
6.壹失足成千古恨
The error committed on impulse may turn out to be the sorrow of a whole life.
7.壹將功名萬古枯
What millions died that Caesar might be great.
8.壹年之計在於春，壹日之計在於晨
Plan your year in spring and your day at dawn.
9.壹人難稱百人意
You cannot please everyone.
10.壹氣呵成
Never make two bites of a cherry.
11.九死壹生
To have a hair-breadth escape.
12.九牛壹毛
A drop in the bucket.
13.人生如夢
Life is but a dream.
14.人生自古誰無死
Death comes to all men.
15.人不可貌相
Appearances are often deceptive./Never judge a book by its cover.
16.人山人海
A sea of faces：How many people are there in the stadium? Believe it or not, a sea of faces.
17.人雲亦雲
Echo others’ words.
18.人面獸心
A wolf in sheep’s clothing.
19.人言可畏
Opinion rules the world.
20.十年風水輪流轉
Every dog has its day.
21.十全十美
Leave nothing to be desired.
22.十拿九穩
Win something in the bag.