The complete form of English is relative to the abbreviated form. For example, the complete form of can't is can not.
You have = you have.
He = He has.
not yet
Want = want
intend to go to...
An English abbreviation can be shortened in any way and will consist of some letter parts.
But abbreviations can also bring trouble, because abbreviations may represent different meanings in different industries, so writing a complete table can avoid misunderstanding.
Extended data
Commonly used:
In the year of the Lord; Since the birth of Christ
Morning, before noon.
April. April
August. August
Avenue. Dadao boulevard
Art BABachelor
BC, BC
bachelor of science
By the way
degree Celsius
cubic centimeter