With some degree of confidence, I'm working with a reliable spring and then I will get the mass of the elephant.

这时我就对弹簧有信心了,我用的是一个可靠的弹簧,我能测出大象的质量

耶鲁公开课 - 基础物理课程节选

I'm optimistic about the audio equipment and about our slide material and things such as that.

我对我们的音响设备,和我们的投影材料等都很有信心

耶鲁公开课 - 聆听音乐课程节选