The status of natural gas chemical industry and the development of chemical technology inland and abThe status of natural gas chemical industry and the development of chemical technology inland and ab
它们控制了中国的海关和对外贸易，控制了中国的交通事业（海上的、陆上的、内河的和空中的）。
The status of natural gas chemical industry and the development of chemical technology inland and abThe status of natural gas chemical industry and the development of chemical technology inland and ab
它们控制了中国的海关和对外贸易，控制了中国的交通事业（海上的、陆上的、内河的和空中的）。
The status of natural gas chemical industry and the development of chemical technology inland and abThe status of natural gas chemical industry and the development of chemical technology inland and ab
它们控制了中国的海关和对外贸易，控制了中国的交通事业（海上的、陆上的、内河的和空中的）。
They are studying chemical technology.They are studying chemical technology.
他们在研究化学工艺学。
