The link below is a brief demonstration of the 1st section of the Second form of Wing Chun – Chum Kiu. Chum Kiu means seeking bridge/sinking bridge 尋橋/沉橋. ‘Bridge(s)’ in a Chinese Martial Art context refer mainly to the whole arms, but can includes the legs. In addition, the ‘bridge’ can be term as ‘short-bridge 短橋’ or ‘long bridge 長橋’: short bridge refer to FOREARM and long bridge refer to WHOLE ARM.
You would noticed that there is ambiguity between whether it is seeking or sinking and in Chinese, though different function; both have the same pronunciation but different characters except for the bridge part(obviously)! The reason is being that through many generations of Wing Chun history, some Sifus believed it is seeking to find an opening while other believed it is sinking to destroy an opponent’s defence and as a result, you may see both meanings illustrated in some articles somewhere but usually from different Sifus!
Personally, I felt that both meanings are correct – to seek and opening and with intent energy to break or sink to destroy the opponent’s protective barrier. Chum Kiu without footwork is meaningless and the practitioner need to understand forces that work within the form – things like appropriate angles, weight distribution, how to generate power, balance, knowledge and awareness.
If you study really hard in Chum Kiu and practice diligently and frequently throughout your life – then it is usually enough for your self defence. The rest can be view as various enhancement of the art of Wing Chun. So, study it well!
https://cambridgewingchun.files.wordpress.com/2021/06/1st-section-of-chum-kiu.mp4