fiddle around: 随便捣鼓
He likes to fiddle around with old cars.
他喜欢摆弄旧轿车。
Pessimists, the mandarin says, reckon "we're just going to fiddle around and miss our opportunities."
该官员说，悲观者认为“我们是在浪费光阴，坐失良机。”

be supposed to: 应该、被认为
Community organizers are supposed to speak truth to power.
公众的组织者应该向权力集团讲真话。
Fear and greed are supposed to govern financial markets.
恐惧和贪婪被认为控制着金融市场。