Speaking of behavior, I have to maintain a fertile learning environment in here. We've got round numbers in excess of 400 people sitting here, so I expect certain things here, and that's how we're going to get along.

说到行为，我要维护一个良好的学习环境,我们的人数有点多,400人坐在这，所以，我期待一些事情，那就是我们相处的方式。

麻省理工公开课 - 固态化学导论课程节选

I want to maintain a fertile learning environment.

我希望维护一个良好的学习环境。

麻省理工公开课 - 固态化学导论课程节选

And what this is in a very general sense is the learning of an association between one stimulus and another stimulus, where stimulus is a technical term meaning events in the environment like a certain smell or sound or sight.

一般来说,经典条件作用是指在一个刺激,和另一个刺激之间形成联结，这里的刺激是一个专业术语,意思是环境中出现的事件,比如某种味道，声音或景观。

耶鲁公开课 - 心理学导论课程节选