Primary, secondary and tertiary carbon atoms and hydrogen(伯,仲,叔碳原子 和氢原子 Quaternary carbon(季碳)(4°C CH3 CH H3C—C—CH2-CH—CH3 Tertiary carbon(叔碳)(3Cand3H) CH3 Isooctane Secondary carbon(仲碳)(2°Cand2°H Primary carbon(伯碳) and primary hydrogen(伯氢)(1°Cand1H)Primary, secondary and tertiary carbon atoms and hydrogen (伯，仲， 叔碳原子 和氢原子） H3C C CH3 CH3 CH2 CH CH3 CH3 Isooctane Primary carbon （伯碳）and primary hydrogen (伯 氢 ） (1 o C and 1 o H) Quaternary carbon (季 碳 ） (4 o C) Secondary carbon （仲碳) (2 o C and 2 o H ) Tertiary carbon （叔碳）(3 o C and 3 o H)