They say babies should be examined when their first teeth appear -- usually at around six months.

VOA: special.2009.03.11

So, let's go ahead and define our variables here, they should be familiar to us. We have the mass, first of all, me m is equal to m e, so that's the electron mass.

让我们继续定义这些常数,我们对这些应该都很熟悉了，首先，我们有质量，m等于。

麻省理工公开课 - 化学原理课程节选

So in that sense, they should be the first to take action, no question.

所以从这一点来说，毫无疑问他们应该首先采取行动。

全球变暖和发达国家 - SpeakingMax英语口语达人

For example,in first grade, students should be asking and answering questions about something they read.

VOA: special.2010.03.25

They say the first shipment from the warehouse should arrive in Haiti in a few days.

VOA: standard.2010.01.18