A stock option gives the holder the right to buy or sell the underlying stock at a fixed price for a specified period of time.

股票期权使得持有者有权在特定时期里以一个固定价格买卖底层股票。

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This kind of swap gives the party who pays at fixed rate the right to cease swap before a agreed period. It also means that the party paying at fixed rate buy the option of swap.

这种互换给与支付固定利率的一方在双方约定的期限以前终止互换的权利，也就相当于支付固定利率的一方购买了互换的买方期权。

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Or perhaps you could engineer a lease option, whereby a renter can choose to purchase the house after a fixed period if he has the wherewithal?

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