音标: 英 ['welhed] 美 ['welhed]
1. Oil field workers switching out a wellhead sparked an explosion.
油田工人关闭了一处井口 引起了爆炸
2. It starts when the oil and the gas leave the wellhead and it keeps on being a problem at every step along the way.
而始於石油和天然氣離開鑽井的那一刻 它會在之後的每一個環節造成問題