All the problems have been solved.

所有的问题都解决了。

youdao

The problem has already been solved。

问题已解决。

《新英汉大辞典》

The problem has been solved satisfactorily at last.

问题终于完满解决。

《新英汉大辞典》

Many people believed the problem of slavery had been solved.

VOA: special.2009.04.09

I don't think, some do, that the question of cultural relativism has been solved.

虽然有些人持相反观点，但我觉得,文化相对主义这个问题并没有被解决。

普林斯顿公开课 - 人性课程节选

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