尝试保持你的头和躯干正好在水面下，只有很小的起伏波动。

Try to keep your head and torso right at the surface, with very little up-and-down-motion.

youdao

尝试保持你的头和躯干正好在水面下，只有很小的起伏波动。

Try to keep your head and torso right at the surface, with very little up-and-down-motion.

youdao