首先

First, you have to drain the container of all the old oil.

首, 你得从油箱中把所有陈油都抽去。

One of the first steps taken was the compilation of a report.

首采取步骤之一是写一份报告。

The formation-types are first rearranged into four major biochores-forest, savanna, grassland , and desert.

首把群系型重新排列成四个主要生态区——森林、稀树草原、草地和荒漠。

Why did you choose basketball in the first place?

你为何首选择篮球呢?

First, he had to establish his credentials as a researcher.

首，他得证明自查员资格。

For openers, I don’t think his work is very original.

首，我觉得他作品并无原创性。

They first react with water to produce the silane triol, releasing alcohol as a by-product.

它们首可与水反应，产生硅三醇，释放出副产物乙醇。

The content of any article needs, first of all, to be relevant to the reader.

首，任何文章内容都必须适应读者需要。

The boy justified himself by saying he did not begin the fight.

这个男为自辩护说他没有首动手打人。

You have first got to motivate the children and then to teach them.

你首得激发学习兴趣, 然后再去教他们。

German unity depends first of all on the German people.

德国统一首靠是德国人民。

A knowledge of her upbringing is basic to an understanding of her books.

要读懂她书就要首了解她成长经历。

He was above all a good and tireless writer.

他首是一位优秀、不知疲倦作家。

Plutonium was first discovered in a Berkeley lab (as were the aptly-named berkelium and californium).

铂就是首在巴克利实验室发现（确切名字该叫巴克利姆或加利福利姆）。

Delhi was first and foremost a barracks town.

德里首是、也主要是一座军营城。

Chiefly, I ask you to remember to write to your elderly mother.

首,我要你记住给你年老母亲去信。

The first clue is by the famous Italian gastronome Giuseppe Maffioli.

线索首来自著名意大利美食家GiuseppeMaffioli。

The first being a skirt type garment (dhoti), with a blouse (choli) and scarf.

首是裙样式衣服（长裤），还有上衣（露出肚脐紧身衣）和围巾。

First cut off the water flow from the boiler.

首切断来自锅炉水流。

First, there is speciation (species-splitting or cladogenesis), caused by geographical isolation or some other mechanism.

首，因地理隔离或其它一些机制导致物种形成（物种分裂或系枝进化）。