一级的英文：
stair

"Step by step, the ladder is ascended"
梯子是一级级爬上去的

Primary underwriters of government securities.
国债一级自营商

She was awarded a first-class degree in English.
她获得一级优等英语学位。

He decided to appeal to a higher court.
他决定向上一级法院上诉。

Screening and sedimentation are the two types of primary treatment used for textile wastes
筛滤和沉淀是用于纺织废水的两种一级处理方法。

In this treatise, we emphasize first-order splines
在这一处理中，我们强调一级样条。

Wang is not. A magnetic resonance imaging exam on his right leg revealed a Grade1 hamstring pull Saturday morning.
王建民不是。星期六早上的核磁共振检查后显示他的右小腿肌腱是一级拉伤。

The lubricant specialist Castrol is the new technical sponsor of the Williams Renault Formula One team.
润滑油专业制造商嘉实多将是威廉姆斯·雷诺特一级方程式车队的新技术赞助商。

Well, we send all the first-class mail by plane to the East Coast, so you don't need an airmail stamp.
是这样，我们寄到东海岸的一级邮件全部用飞机传递，所以你不需要贴航空邮票。

Hakkinen of Finland had his first test in the 1996 Mclaren Formula One Car at the Estoril track in Portugal 0n Thursday.
星期四,芬兰车手哈基宁在葡萄牙埃斯图里尔车道进行他的1996年麦克拉伦一级方程式赛车首次试车练习。

She has trouble navigating the stair.
她上下台阶有困难。

They went clumping up the stairs.
他们拖着沉重的脚步走上楼。

She pegged down the stairs.
她急忙下楼。

There was a woman mopping the stairs.
一个女人在拖楼梯。

She was standing at the top of the stairs.
她站在楼梯的顶端。