Optimized design for the vent hole was carried out.

筒上有孔用于通气孔。

And a valving element 33 closing said second vent hole 32 in a manner capable of opening and closing said second vent hole 32 only.

以及阀元件33，所述阀元件33以能够打开和封闭仅仅所述第二通气孔32的方式封闭所述第二通气孔32。

I know not what vent-hole daylight habitually illumined his soul.

我不知道是怎样一种黯淡的光经常照着他的心。

Experts say the poor hippo must have been startled during the journey, leading him to jump through the vent hole of the truck.

专家表示这只可怜的河马一定是在卡车行驶中受到惊吓才做出跳车这种大胆举动。