Explosions, though infrequent, are an occupational hazard for coal-miners.
Explosions, though infrequent, are an occupational hazard for coal-miners.
矿井爆炸虽然不常发生, 但却是煤矿工人职业中的危险.
Explosions, though infrequent, are an occupational hazard for coal-miners.
矿井爆炸虽然不常发生, 但却是煤矿工人职业中的危险.