日常美语短句第 20 课：Reflexes 反射动作

It's a conditioned reflex. 这是种不经思索的反射动作。

I did it by some unknown force. 有种莫名的力量， 驱使我做了这件事。

She had obviously done it out of impulse. 显然她是一时冲动才做出这种事。

On the spur of the moment, I decided to fly to Rio. 我一时心血来潮，决定飞往里奥 （巴西的旧首都）。