“Well, you're losing your grip, then! ” sneered Malfoy.

“哼，你正在失去对他的控制！”马尔福讥笑道。

Katherine, you are losing your grip here.

凯瑟琳 你还没搞清楚情况。

If you're losing your grip, you're not really holding things together properly.

如果你失去了控制力， 你就没有真正正确地把东西放在一起。