IfGreeksandTurkshadnothelpedeachotheraftertheearthquakesfiveyearsago,

If Greeks and Turks had not helped each other after the earthquakes five years ago,they____ mortal enemies instead of friendly neighbors later onA.would have beenB.might beC.should have beenD.must have been

B解析考查错综时间的if非真实条件句，从句是和过去相反，用过去完成时，主句是和将来相反的，用would/might/should do，句意是：如果希腊和土耳其人没有在五年前地震后互相帮助,他们将成为不共戴天的敌人,而不是以后的友好邻邦。选B。

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