It's vibe, it's X factor, it's undefinable.

它是围，它是未知因素，它是法定义。

The exclamation was always followed by an undefinable look cast upon him in return by the old servant.

声惊呼之后，老仆人总是用难以形容目光回敬他。

At that moment, I was grateful for music itself, for the sheer existence of this elusive, undefinable phenomenon that seems to ignore our brains and go straight to our hearts.

那刻，我感谢音乐本身，感谢这难以捉摸、法定义现象存在， 它乎视我们大脑， 直达我们内心。

The longing was with him day and night, an incessant undefinable craving, like the sudden whim of a sick man for food or drink once tasted and long since forgotten.

这渴望日日夜夜伴随着他， 持续不断法形容渴望，就像个病人突然心血来潮想要吃过次但早已忘记食物或饮料。

The undefinable sense we were speaking of is a ticklish instrument, easily thrown out of gear by a sudden fall of temperature; and the sharpest experts grow shy and self-distrustful when the cold current of depreciation touches them.

我们所法定义感觉是怕痒工具，很容易因温度突然下降而失灵；当贬值寒流触及他们时，最敏锐专家会变得害羞和不自信。

It was only within a week that she had felt in him the undefinable change that made her restless in his absence, and as tongue-tied in his presence as though it were she who had a secret to keep from him!

仅仅在周之内，她就感觉到他身上发生了法形容变化，这变化让她在他不在时候焦躁不安，在他面前张口结舌，好像她有什么秘密要瞒着他！