Europe's biggest economy,Germany, last week banned some speculative trading and has indicated it may do so in the longer term.

VOA: standard.2010.05.26

I mean, to the extent that you're making these short-term bets against your long-term policy, it requires trading and trading is expensive.

我的意思是,在长期策略下进行短期操作,就需要进行交易,而交易是昂贵的

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