It is a necessity. He believes that the first priority of any climate bill enacted by Congress must be to put a cap on global warming gases.

VOA: standard.2010.06.14

And, what we will do next day is we will look at the consequences of such an energetic set up, and rationalize that when ions form, by necessity we must form ionic crystals.

明天我们要做的是,观察一下,这样一个充满活力的创造的结果，然后合理地解释要想得到离子，我们必须先得到离子晶体。

麻省理工公开课 - 固态化学导论课程节选

That doesn't, by the way, happen until 1934 when it became a kind of pronouncement of necessity at the International Soviet Writers Conference on that occasion.

直到1934年4,国际苏联作家会议,发表了类似的声明。

耶鲁公开课 - 文学理论导论课程节选

(...) He said the Democratic initiatives introduced by our government have been met with praise and he said the necessity of taking concrete steps alongside this wide ranging process is emphasized.

VOA: standard.2009.10.15

The first stage proposed by Adeimantus is the simple city, what he calls the city of utmost necessity.

由，Adeimantus，提出的第一个阶段是,简约之城，他所谓的本需之城。

耶鲁公开课 - 政治哲学导论课程节选