luó / mào / méi / yǒu / nǐng / jǐn / jī / qì / yùn / xíng / shí / jiù / huì / fā / chū / yì / xiǎng螺帽没有拧紧,机器运行时就会发出异响。The nut was not tightened, so the machine made a strange noise while running.