你要采取措施，以防不测。

You should make provision for things going wrong.

虽然那天阳光明媚，我父亲还是带上了雨伞以防不测。

Although the sun was shining the other day, my father took the umbrella with him to be on the safe side.

计划去机场的时候，我会算进一段“缓冲时间”，以防不测，像是堵车啊，爆胎啊。

In planning my drive to the airport, I'll factor in a "cushion" to allow for the unexpected, such as heavy traffic, or a flat tire.

如果没有购买全车盗抢险，可以考虑花100元左右投保一个月的全车盗抢险以防不测。

Without the purchase of the entire car Daoqiangxian could be considered spent 100 yuan a month throughout the insured vehicle Daoqiangxian to trial.