1.If you have less money than usual, you may have to "tighten your belt" -- you may have to live on less money and spend your money carefully.
tighten one's belt 节衣缩食
I have to tighten my belt this week.
这个星期我不得不勒紧裤腰带过日子 。
I spent too much money last month. I better tighten my belt this month or I will be in trouble.
我上个月花太多钱了,我这个月最好缩衣节食点,否则我就糟糕了!
2.Yet, when it comes to my own money, I spend it "at the drop of a hat" -- immediately, without waiting.
at the drop of a hat 立即
He used to fight at the drop of a hat.
他以前动不动就打架 。
I love to travel, I'm ready to go at the drop of a hat.
我喜欢旅游,我准备马上就去 。
3.He is like a person who does magic tricks. We say "he has a card up his sleeve."
have a card up one's sleeve 胸有成竹
Bill always has a card up his sleeve, so when his first plan failed he tried another.
比尔经常留有一手, 所以当第一个计划失败后, 他就试行第二个 。
Mr Smith always has a card up his sleeve.
史密斯先生总是胸有成竹 。