1. It later became apparent that rabbits were developing a degree of resistance to this disease, so that the rabbit population was unlikely to be completely exterminated.
    后来，明显看出，兔子对这种疾病已产生了一定程度的免疫力，所以兔子不可能被完全消灭。

2. It was necessary first to arrive at that degree of sophistication where we no longer set our own belief against our neighbour´s superstition.
    我们首先需要达到这样一种成熟的程度：不用自己的信仰去反对我们邻居的迷信。