He walked two hours at weekends to the market to buy different things to sell around his school.

他周末要走两个小时的路去市场买各种各样的东西，以便在学校周围卖。

youdao

Never buy all at once. Never sell all at once.

不要一下子全部买入，也不要一下子全部售出。

youdao

At 19 he began to buy and sell properties.

19岁的时候他就开始购买和出售地产。

youdao

For example they buy at 100 an empty house and they sell after 5 years at 150, like the stock exchange.

VOA: standard.2009.10.27

Neither do the dealers determine the term structure; the dealers have to buy and sell at prices that are in the market.

中间商也不能决定,中间商只能按照市场价进行交易

耶鲁公开课 - 金融市场课程节选

With this discipline, so goes the story line, you are forced to sell at the top and buy at the bottom.

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Of course, the reverse is true, where you will never be able to buy at the bottom and sell at the top.

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It can buy and sell assets at will, and adjust the IOR rate at will.

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