the process whereby heavy molecules of naphtha or petroleum are broken down into hydrocarbons of lower molecular weight (especially in the oil-refining process)
造句
Printing business cards on a thirty-inch press is using a sledgehammer to crack a nut. 在30英寸印刷機上印刷名片簡直是大材小用，得不償失。
近義反義詞
crackly
crack
cracked stock
cracks growth
crack and rut
cracking tube
crack pattern
crack a crust
cracked beams
crack spacing
crack control
crack pouring