1. I took an umbrella as a precaution.
    我带了一把伞以防下雨。

2. We have taken necessary precautions against fire.
    我们已采取必要的防火措施。

3. Take precautions against fire!
    谨防火灾！

4. He took the precaution of locking his door when he went out.
    当他外出的时候谨慎地锁上门。

1.

1. 防范：总之,在进行转基因食品安全性评价时遵循了以下原则:实质等同性原则(substantial equivalence)、预先防范(precaution)的原则、个案评估的原则(case by case)、逐步评估的原则(step by step)、风险效益平衡的原则(balance of benefits

2. precaution

2. 预防：<中国日报>>近日以 预防(Precaution) 为标题,刊登了一系列全世界民众戴口罩防范甲型(H1N1)型流感病毒的图片... 2009-05-07

1. 预防措施；防备
    A precaution is an action that is intended to prevent something dangerous or unpleasant from happening.

precaution在线翻译

    e.g. Could he not, just as a precaution, move to a place of safety?...
           就算仅仅是为了以防万一，难道他就不能挪到安全的地方吗？
    e.g. I had taken the precaution of doing a little research before I left London...
           我已在离开伦敦前进行了准备，做了些调查研究。

1. a precautionary measure warding off impending danger or damage or injury etc.

    e.g. he put an ice pack on the injury as a precaution
           an insurance policy is a good safeguard
           we let our guard down

    Synonym: safeguardguard

2. the trait of practicing caution in advance

3. judiciousness in avoiding harm or danger

    e.g. he exercised caution in opening the door
           he handled the vase with care

    Synonym: cautioncareforethought