Drop your jaw which will cause your mouth to open.

放松你的下颚让你的嘴巴打开。

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Modern large-mouthed snakes, such as boas and anacondas, can eat large prey because their jaw joints are positioned well behind their skulls, allowing the snakes to open their mouths very wide.

现代阔口蛇，像蟒蛇和水蟒，能吃大的猎物是因为它们的颌关节恰位于头骨的后面，能使蛇的嘴张得非常宽。

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Unlike modern snakes, s. indicus lacked jaw joints that allowed it to open its mouth incredibly wide, so it relied on its large overall body size to prey on the fledgling dinosaurs.

有别于现代蛇类，Sanajeh indicus蛇不具备让它血口大张的颌骨关节，所以只能依靠其庞大身躯来猎食恐龙幼仔。

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And if anyone actually ever paid them, their jaw would drop open because they don't expect to get that at all.

NPR: 6 min 38 sec

Mr Warren could hardly look less like Mr Graham he has a beard rather than a lantern jaw and sports open-necked shirts, mostly of the Hawaiian variety, rather than a suit and tie.

ECONOMIST: Lexington

World Peace grabbed Knight around the neck and struck him in the jaw with the knuckles of his mostly open hand on Sunday with 1:43 left in the first half of the Lakers' 98-97 win over the Pistons.

WSJ: World Peace suspended, Howard out for Lakers