In motion, the body is light and agile, every part is coordinated, moving in unison (guan chuan.)
Rouse  the Qi, with the spirit of vitality(shen) concentrated internally.
Avoid deficiency and excess; avoid projections and hollows; avoid separation.

Issuing force is rooted in the feet, issued through the legs,
directed by the waist, and issues in the hands and fingers.
The feet, legs and waist must act as an integrated unit
so that whether advancing or withdrawing you will be able to obtain strategic advantage.
Failure to obtain a superior position and create a strategic advantage leads to the body movement being in a state of disorder and confusion.
Correct this flaw by minding the legs and waist.

Likewise, upwards and downwards, forwards and backwards, left and right,
to move upward, direct  the mind-intent (yi) downward,
just like the motions of lifting a heavy object.
If there is movement above, it must originate below;
if there is advance, there must be withdraw;
if there is left, there must be right.
If the initial intent is upwards, you must first have a downward intent.
If you want to lift something upwards, you must first have the intent of pushing downwards.
Then the root will be severed; it will topple quickly.

Clearly distinguish the substantial and insubstantial.
Everything contains a substantial and insubstantial element.
 The entire body is held together joint by joint.

What is Chang Chuan (Long Boxing?)
It is just like a long river or great ocean flowing smoothly and continuously.

The Thirteen Postures of Ward-Off(peng,) Roll-Back (lu), Press (ji,) Push (an), Pull (tsai,) Split (lie,) Elbow-Stroke (zhou) and Shoulder-Stroke (khao) are known as the Eight Diagrams (Bagua).

Advance-Step, Withdraw-Step, Look-Left, Gaze-Right and Central Equilibrium are known as the Five Elements/Phases (Wu-Hsing.)

Ward-Off, Roll-Back, Press and Push are then (the trigrams,) Qien, Kun, Kan and Li, the Four Cardinal directions.

Pull, Split, Elbow-Stroke and Shoulder-Stroke are then, Sun, Chen, Tui and Ken, the Four Diagonal/corner directions.

Advance, Withdraw, Look-Left, Gaze-Right and Central
Equilibrium are then, Metal, Wood, Water, Fire and Earth.

Joined together they become the Thirteen Postures.