1、do good to sb/sth 表示“对某事/某人有好处”
eg:Riding a bicycle will do good to your health.骑自行车有益身体健康.
Riding a bicycle will do good to me.骑自行车对我有好处.
2、do sb good 表示“对某人有好处”
eg:Riding a bicycle will do me good.骑自行车对我有好处.
3、do sb harm = do harm to sb = do bad to sb 表示“对某人有坏处”
4、do sb bad 这种形式很少出现,基本上我就没见过,所以为了不必要的麻烦,"对某人有坏处"还是就记忆成do bad to sb,do harm to 和 do sb harm,不要用 do sb bad.