If you go to brokers, whether the market is up or down, he can earn the spread.

要是你去找经纪人，不管市场是涨还是跌，他都可以赚取价差。

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Steady markets would give investors fewer reasons to deal, and so traders would have less chance to earn the spread between sell and buy prices.

稳定的市场会减少投资者交易的次数，而且交易员赚取买卖价差的机会也会减少。

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Market makers earn their livings from the spread between buying and selling prices.

炒股者赚取股票买卖的价格差。

《柯林斯英汉双解大词典》

But this is now drying up, because new rules imposed by the Securities and Exchange Commission have shrunk the profits that market makers earn on the spread between buy and sell prices.

ECONOMIST: Stockbroking

Recent cuts in short-term interest rates should help banks, by steepening the yield curve (the difference between long and short rates) and thus boosting the spread they can earn.

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And when interest rates rise they can increase the interest rate spread they earn.

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