So, at last, when I could hold out no longer, I resolved to lay the case before my uncle, as prudently and as cautiously as possible, just under the form of an almost impossible hypothesis.

所以，最后，当我再也坚持不下去的时候，我决定尽可能谨慎、谨慎地把这个案子摆在我叔叔面前，只是以一个几乎不可能的假设的形式。