Suite for solo cello No. 1 in G major, BWV 1007: Prelude.

Just search the part in brackets on Baidu. You can also find it from the link below:

/m?f=msamp;tn=baidump3amp;ct=134217728amp;lf=amp;rn=amp;word=B0CDBAD5B4F3CCE1C7D9amp;lm=-1

This piece comes from Bach's unaccompanied cello suites (commonly known as "Grand Cello Suite"), one of six pieces, and this is the first. These are all untitled pure music, giving people unlimited room for imagination. There are some dance pieces in the cello suite, which are just musical styles and probably not really composed for dancing.

Bach's A cappella is an important work of Bach and occupies an important position in today's cello solo repertoire. Playing them and releasing recordings of them is a sign of a cellist's maturation. Casals, Stark, Rostropovich, Yo-Yo Ma, and Wang Jian have all recorded the song.