be a fool to oneself

1. 好心没好报
   He's a fool to himself.

   他好心没好报。

fool about

1. 虚度光阴
   He just fools about all day long.

   他整天闲荡。

fool away

1. 浪费
   You are fooling away your money.

   你这是在浪费钱。

fool with

1. 戏弄
   He was fooling with the girl's love.

   他在玩弄那姑娘的感情。

make a fool of oneself

1. 出丑
   He made a fool of himself.

   他出了个大洋相。

make a fool of sb.

1. 愚弄某人
   Jane always makes a fool of her younger brother.

   简老是作弄她弟弟。

play/act the fool

1. 装傻
   The father told the boy to stop playing the fool.

   父亲叫孩子不要再装疯卖傻了。

• be no (or nobody's) fool
  be shrewd or prudent.
• make a fool of
  trick or deceive (someone) so that they look foolish.
  ▸ (make a fool of oneself) appear foolish through incompetent or inappropriate behaviour.
• more fool ——
  the specified person is behaving unwisely.