Chinese Characters'Structure

The characters are written within the framework of a square, and there are several basic structures.Characters are defined as being either basic characters or compound characters.

a) Basic and compound characters

Characters are defined as being either basic characters or compound characters.
Less than 5% of all characters are basic and over 95% are compound, depending on the number of characters included. The proportion of basic characters in a 500 high-frequency character list is much higher, representing over 30% of characters included in the list.
Basic characters are not divisible into two sides. They contain only one component. Compound characters contain two or more components, and usually show clear division into two sides: the radical and the stem.

b) Structures and sides

The structures or sides in compound characters are usually easily identified, as most sides do not touch or intersect; they are separate. However, in some cases the sides connect, and in rare cases intersect. In some characters the sides are not evident and the character is comprised of three or more individual components i.e. no two components represent an identifiable side.
Structure types: characters can be arranged into ten structure types. Most compound characters (around 65%) have a left-right structure. Around 25% have a top-bottom structure. Less than 10% are enclosed; on two, three or four sides.
Of the two sides, the first, Side A, is the left, top or enclosing side, and is usually written first. There are two exceptions: the box (structure 7) and two key components in the enclosure (structure 4) which are always written last.
Most radicals are located at Side A. There are some particular exceptions to this rule; see Key concept 5, Character functions. A full explanation of the ten structure types is provided in the table: Character structures and sides.

C）Composite structures

Some compound characters have multiple components and do not show clear division into two functioning sides (apart from the radical, the remaining component set is not and does not function as a stem). These are called composite structures. These characters are considered to be a sequence of components, not a combination of two sides.
Four key structures are evident in this category:

1. Three components, arranged horizontally or vertically

2. Two above and one below, or one above and two below

3. Four or more components, in a balanced arrangement

4. Three components, repeated in a pyramid