When small creatures swim past, they bend the hairs on the bladder, causing a flap to open.

当小生物游过时，它们会弯曲膀胱上的毛发，导致膀胱瓣打开。

youdao

Couldn't you just open a flap or something and let it out?

你难道不能在(宇航服上)开个口之类的，把气味儿放出来么？

youdao

I had left my tent flap half open during the night, and awoke at 7 a.m. to a stream of soft desert light.

夜里我把帐篷的门帘半开着，次日上午七点我在沙漠柔和的晨光中醒来。

youdao

Fingers appeared, pressing the flap open.

NEWYORKER: Bravado

That extra attention to detail has already begun at the Ferrari factory as the team's engineers solved the problem with Alonso's faulty drag reduction system (DRS) -- an overtaking aid which increases the car's straight-line speed by flipping open the top flap of the rear wing -- the day after the Bahrain Grand Prix.

CNN: Ferrari boss: 'We have to be perfect'

Dasatinib can gum up the protein when the flap is open or closed.

FORBES: The Race Is On