题目内容：

this would solve the problem.That's how the problem___solved.1 would been 2 would be
3 would have been 4 had been

优质解答

选2.
首先,这里的would是助动词,后面应该接动词原形,就像前一句this would solve the problem一样,所以排除1,4..然后3 would have been 一般用在虚拟语气,表示与过去事实相反,这里明显不是虚拟语气.所以选2,整句话的意思是：这就是解决这道问题的方法.
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