Definition
With the head leading or going in front of the rest of the body.
头先，头部先行
He jumped head first into the cold river.
他头朝下跳进了冰冷的河里。
She accidentally fell head first down the stairs.
她不小心头朝下从楼梯上摔了下来。
He slid down the water slide head first, splashing water everywhere.
他头朝下从滑水道滑下来，水花四溅。