Write your letter and seal it in a blank envelope...

Troops have sealed the borders between the countries.

军队已关闭了两国边界。

The floors had been stripped and sealed with varnish.

地板上东西挪空，涂上了清漆。

Such a visit may set the seal on a new relationship between the two governments...

这样的一次访问可能会使两国政府间确立新关系。

a sealed bid (= one that is kept in a sealed envelope and therefore remains secret until all other bids have been received)

密封（投）标

The discovery of new evidence sealed his fate (= nothing could prevent what was going to happen to him) .

新发现的证据决定了他的命运。

A woman picks them up and seals them in plastic bags.

一个女人把它们捡起来放入几只密封的塑料袋中。

Is the letter sealed?

信封口了 吗 ?

She sealed the letter.

她把信封上了.

Windows are usually sealed off.

窗户通常是封闭的。

There are many such casual associations of species.

有许多这样偶然的种类组合.

They should not conflict with common mental associations.

他们不应与人们感官上共同的联想相违.

The power of words, then, lies in their associations -- the things they bring up before our minds.

——文字的威力就在于它们使人产生的联想 —— 那些令我们想起的某些事物.

Interest groups are free associations.

利益集团都是自由的社团.

In the Braun-Blaoquet school the description of synusial associations was not confined to cryptogam communities.

在 Braun -Blaoquet学派中,层片群丛的描述不限于隐花植物群落.

Some associations provide homes to buy or part-buy.

一些协会提供可以整套购买或部分购买的房子。

Associations are more likely to occur when the partial pressure is high.

当水汽分压提高时,缔合更容易发生.

Some intense associations of a most distressing nature were vividly recalled, I think.

我认为是某种最痛苦的紧张联想又在记忆中活跃了起来.

Every successive element of fluid undergoes the throttling process in a continuous stream.

在连续的流动中,每一流体元相继地经历节流过程.

There's a saying -- woman undergoes numerous changes when she grows up.

俗话说女大十八变.

The public loses interest, and undergoes reaction.

人们不仅感到扫兴, 而且还起了反感.