coal to olefin的用法和样例：
- With Luzhou as the focal point, speed up development of coal gasification, ethanol and ethyl fuels, coal to olefin project and introduction and development of its downstream technology and products to promote the establishing of Chemical City in Luzhou.
- We have enough coal to see the winter out.
- Conversion of your heating system from coal to gas will be costly.
- She uses tongs to add coals to the fire.
- They burned coal to heat the room.
- She used the tongs to add coal to the fire.