1.If sb had done sth(坏事), sb would never have done sth(好事).
If Hugh Miller, after toiling all day in quarry (采石场), had devoted his evenings to rest and recreation, he would never have become a famous geologist.
2.Sb would never have done sth(好事1) , never have done sth (好事2), if sb had done sth (坏事)
sb永远不可能做sth， 永远不可能做sth， 如果某人过去做了某件不好的事
The celebrated mathematician, Edmund Stone, would never have published a mathematical dictionary, never have found the key to science of mathematics, if he had given his spare moments to idleness.
3.Had sb done sth(坏事) ， sb would never have done sth (好事)
Had the little Thomson, allowed the busy brain to go to sleep while he tended sheep on the moutain, instead of considering the stars by a string of beads, he would never have become a famous scholar.