Could it be said that it is impossibleof attainment?
难道这是办不到的吗？
《新英汉大辞典》
2
June, 1848, let us hasten to say, was an exceptional fact, and almost impossibleof classification, in the philosophy of history.
让我们赶快说出来，1848年六月是一次独特的事件，几乎不可能把它列入历史的哲学范畴中去。
3
Although an older woman could be distinguished from a younger one by her face, regarding only what is below the girdle, it is impossibleof two women to know an old from a young one;