yóu yú / àn bà / bú yì / chá jué / chuán zhī / háng xíng / shí / jí yì / fā shēng / pèng zhuàng / shì gù由于暗坝不易察觉,船只航行时极易发生碰撞事故。Because submerged dams are hard to notice, ships are very likely to collide with them while navigating.