Others last for months or even years. There is no clear way of predicting at the present time how long this activity might go on for."

VOA: standard.2010.04.16

This is the present value of $1 in one time period, which I'm taking to be a year.

这就是一美元在一段时期内的现值,我只是将一美元持有一年

耶鲁公开课 - 金融市场课程节选

The plan, every time, is to predict the future given the present.

无论何时,我们的做法都是根据现状来预测未来

耶鲁公开课 - 基础物理课程节选

If several of these conditions are present at the same time, a person's body temperature may rise above safe levels.

VOA: special.2010.07.27

The danger is that it's being purified from patients that have a disease and so you want to make sure that there's not other diseases that are present in that sample at the same time.

危险在于,这是从带有疾病的病人,身上纯化出来,因此你想确保,在那个样本中不会同时,携带其它疾病

耶鲁公开课 - 生物医学工程探索课程节选

Prosecutor Alan Tieger wasted no time, dramatically launching into the case he intends to present.

VOA: standard.2009.10.27