Mouths opened and remained open.
嘴张着，一直张着。
No lie was found in their mouths.
在他们口中察不出谎言来。
We use our mouths to eat and talk.
我们用嘴吃东西和讲话。
They opened their mouths.
他们张开了嘴巴。
They are hippo's mouths.
这些是河马的嘴巴。
