The second one is acoustic koa.

第二个是acoustic koa。

Hawaiian men and women of all ages and social classes participated, riding surfboards shaped from koa, breadfruit, or wiliwili trees.

夏夷各个年龄段和社会阶层的男女都参加了比赛，他们骑思木、包果利利制成的冲浪板。

Boatmaking was so revered that there were specific religious rituals throughout the entire process of building one, starting with selecting the correct koa tree.

造船业是如此受人尊敬， 以至于在造船的整个过程中都有特定的宗教仪式，从选择正确的思开始。