But the threat of terrorism, according to former Yemeni prime minister Abdul Karim al-Iryani, is equally part of the downward economic spiral causing anger on the streets of Sana'a.

VOA: standard.2010.04.20

And very often what that does-- a positive emotion can take us out of this downward spiral and create an upward spiral.

很经常的是-,积极情绪把我们带出下行螺旋,形成一个上行螺旋。

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