lǎo jiù / kuàng jǐng / de / kēng dào / tū rán / bēng xiàn / jiù yuán / rén yuán / lì jí / fēng suǒ / le / rù kǒu老旧矿井的坑道突然崩陷,救援人员立即封锁了入口。A tunnel in the old mine suddenly caved in, so the rescue workers immediately sealed off the entrance.