For such a powerful hunter, the polar bear lives a precarious existence.

然而就是这样强大的猎手其生存却充满了不确定性。

Rising temperatures threaten this precarious environment.

不断上升的气温对本就缺乏稳定性的这一环境无异于一种威胁。

Advocates say the migrants precarious status makes them vulnerable to exploitation.

倡导者说，移民地位岌岌可危，这使得他们很容易受到剥削。

BBC's Daniel Gallas who's based in Sao Paulo says her situation is precarious.

本台驻圣保罗记者丹尼尔·加拉斯表示，罗塞夫地位岌岌可危。

This puts the dinosaur in a very precarious position if it happens to get attacked.

如果圆顶龙在这时遭到攻它会处于非常危险的境地。

Those on precarious part-time contracts are particularly vulnerable to being fired while on maternity leave.

至于那些没有保障的兼职合约员工极有可能在产假期间被解雇。

Their situation is precarious, but cannibalism for them isn't a last-ditch attempt to avoid starvation.

它们的情况很危急，但对于它们来说，同类相食并不是为了避免饥荒的孤注一掷。

They are tracked by a data operation that detects pupils in precarious positions before they quit.

他们被一个数据操作系统追踪，这个数据操作系统可以在他们退学前检测他们的不稳定状态。

Officials at the Jaipur Golden Hospital have told the BBC that the situation continues to remain precarious.

斋浦尔金医院的官员告诉BBC，直到今天早上情况依然很危急。

In a statement, it said the lives of the prisoners are at risk in Colombia's precarious jails.

并在声明中称因哥伦比亚监狱状况堪忧，武装员的生命受到了威胁。

The incident experts say highlighting our precarious dependence on global, just in time delivery using mega ships.

事故专家表示，这突显了我们全球对使用巨型船舶及时交货的过度依赖。

This is what makes our situation so precarious, and this is what makes our intuitions about risk so unreliable.

这就是为什么我们所处的环境是很危险的，这也是为什么我们对风险的直觉是不可靠的。

Your position at that school is already too precarious.

你还没在那学校站稳脚跟。

The precarious state of his country.

祖国形势又危险。

I just figured you knew better, given the precarious position you're in.

我只不过觉得你会更明白事理，鉴于你自己正处在风雨飘摇的境况下。

And the nature of the fossil record tells us that our place on this planet is both precarious and potentially fleeting.

但我们，却有着选择化石揭示了我们在地球上的地位。

There are warnings time is running out to avert a second Chernobyl catastrophe due to the precarious condition of the sarcophagus.

有关方面警告称由于石棺的危险性防止发生第二次切尔诺贝利灾难的时间已经所剩无几。

His choice to become a government witness confined him to a precarious safe house, where the Martinez brothers interviewed him repeatedly.

他选择成为一名政府证，官方将他监禁在一个岌岌可危的安全屋里，马丁内斯兄弟多次在那里采访他。

Particularly precarious with farmworkers is the type of labor they're involved in, if it's shift work vs. ongoing or formal employment.

农场工有一个难确定的要素是他们参与的工种，问题在于他们做的是倒班的工作还是正式工作。

But when he got down to writing, how did he walk that precarious line between fact and fiction while blending them together?

但是，当他开始着手写作时，他是如何在事实和虚构之间那条飘忽不定的线上游走，并将二者融合在一起的呢？