首先，所有现有的氦供应应该被保存下来，并且只有在获得许可的情况下才能释放，医疗用途应优先于其他商业或娱乐需求。

Firstly, all existing supplies of helium ought to be conserved and released only by permit, with medical uses receiving precedence over other commercial or recreational demands.

youdao

首先，所有的动物，如牛、猪和羊，总是排出石灰甲烷气体，这是继二氧化碳之后第二常见的温室气体。

For a start, all animals, such as cows, pigs and sheep, always gas limed methane, which is the second most common green house gas after carbon dioxide.

youdao

首先，所有字段都使用占位符属性，这是一个HTML5特性，因此会一直显示占位符文本，直至该字段获得焦点。

First, all of the fields use the placeholder attribute. This is an HTML5 feature that causes the placeholder text to be shown until that field gains focus.

youdao

What I want you to notice first of all is the kind of reader that's being invoked here for that modernist classic Ulysses.

首先希望你们注意到的是,所有开始阅读现代主义经典,《尤利西斯》的读者。

耶鲁公开课 - 1945年后的美国小说课程节选

Eh, it really is, first of all, government of all institutions can make health care less expensive.

嗯，确实是这样，首先，所有政府机构,都有能力降低医疗费用。

斯坦福公开课 - 经济学课程节选

You take all the risky assets ... and you analyze them first to get their-- you have to do a statistical analysis to get their expected returns, their variances, and their covariances.

你需要对所有的风险资产进行分析,首先要得到它们的-,你必须要做一个统计分析,算出它们的预期收益率，方差，和它们的协方差。

耶鲁公开课 - 金融市场课程节选