Just like people all over the world, people in China traditionally associate luck with various things and numbers. If you remember this, you will gain an understanding of Chinese manners and customs and will not embarrass yourself or your Chinese friends, that is sometime funny!!! I have some story about it...
As a rule in day-to-day life in China, it is customary to regard even numbers as being more auspicious than odd numbers. In China, traditionally gifts are given as a part of the celebration for all occasions. Thus, guests will always give even-numbered presents. As the number:
two (Er)2, usually suggests germination and harmony, at wedding celebrations, decorations are invariably setout in pairs: a pair of red candles, a pair of pillows, and couplets hung on two sides of the hall.
Six, pronounced as 'Liu'6, conveys indirectly its homophony's meaning – Do everything smoothly;
and eight,8 'Ba' in Chinese has a similar sound to 'Fa', which means to make a fortune. All business men favor this number very much.
However four, is the exception to the even number rule as it sounds like 'Si' 4(death). So when people choose car license tags, phone numbers, and room numbers, they try to avoid it.
For odd numbers, seven implies anger and abandon, but nine, sometimes means longevity and eternality.
Based on these notions, it is the fashion for young lovers to send roses. One rose represents that 'you are my only love'; two, 'only we two in the world'; three, the three moving words 'I love you'; and nine, 'everlasting love'.