Variable-interval (VI) Schedule: A schedule of reinforcement in which a reinforcer is delivered for the first response made after a variable period of time whose average is predetermined.
可變——間隔程序表：
Variable-ratio (VR) Schedule: A schedule of reinforcement in which a reinforcer is delivered for the first response made after a variable number of responses whose average is predetermined.
可變——比率程序表：
Vestibular Sense: The sense that tells how one's own body is oriented in the world with respect to gravity.
前庭覺：告訴我們一個人的身體在重力作用下是如何定位的感覺。