First 的用法

一、first 作序数词或形容词用，“第一”、“最初的”、“头几个”讲

1. We shall go to Beijing by highway on the first of May. 我们将于 5 月 1 日由高速公路去北京。
2. The first thing for him to do is to repair the video telephone set. 他要做的第一件事是修理这个可视电话机。
3. I was among the first to arrive. 我属于第一批到达者的行列。
4. She won first place in the race. 她在比赛中获得第一名。（表示名次时，前面的定冠词常不用。）
5. a. This is the first time (that) I have heard of it. 这是我第一次听说这件事。（that 引出的从句中必须用现在完成时。若主句中谓语为 was，则从句内用过去完成时。详见下句。）
   b. That was the first time they had been alone together. 那是他们第一次单独在一起。
6. They haven't the first idea what it means. 他们丝毫不知道这是什么意思。（这里 the first… 作“最初的一点点”讲，用于否定句。）

二、副词 "first" 作“先”、“初步”、“开始时”讲

1. To answer this question, we must first consider a few factors. 为了回答这个问题，我们必须先考虑几个因素。
2. This air is usually dried by first cooling it to a low temperatures, the water condensing out in the form of ice. 这种空气的干燥一般通过先把它冷却到低温来进行，结果水凝结成冰。
3. First think and then speak. 先考虑后说话。（注意 first… and then 前后呼应的用法。）
4. Women and children first. 首先是妇女和儿童。（谦让时用语）
5. She lived in Beijing first and last about ten years. 她在北京前后一共住了十年左右。

三、和 first 搭配的常用短语

at first 起初，(at) first hand 直接地，第一手地；at first sight (或 glance, appearance）乍一看；first and foremost = first of all = first off (后者主要用于口语中) = (the) first thing (in the morning) = in the first place 首先；for the first time 第一次[常作状语]；from the (very) first 从一开始，from first to last 从头到尾； first (或 firstly), secondly, thirdly… 第一，第二，第三…