A precaution is something you do now so that something dangerous or unpleasant is less likely later. You lock the door as a precaution. You take an umbrella as a precaution, even if the sky still looks kind.

A precautionprecaution is something you do now是你現在先做的一件事， so that something dangerous or unpleasant is less likely later好讓之後發生危險或不愉快事情的機會變小。You lock the door as a precaution.你把門鎖上，當作一個預防措施。You take an umbrella as a precaution你帶把傘出門，當作預防， even if the sky still looks kind即使天空看起來還很晴朗。

The word lives in careful advice, medicine, travel, and safety notices; it is serious without being poetic. Though actually, people stretch it a little: “just a precaution” often means “I do not really expect trouble, but I am not willing to look silly if trouble comes.” You usually take precautions (plural) when there are several steps, and you do something as a precaution when there is one extra careful act.

The word lives in careful advice, medicine, travel, and safety notices這個字出現在謹慎的建議、醫療、旅遊和安全公告裡； it is serious without being poetic是嚴肅的字，但不詩意。Though actually不過其實， people stretch it a little人們也會用得寬鬆一點： “just a precaution” often means「just a precaution」常常的意思是 “I do not really expect trouble, but I am not willing to look silly if trouble comes.”「我不是真的預期會出事，但如果真的出事，我不想看起來很傻」。You usually take precautions (plural)通常有好幾個步驟時，你會用複數 precautions， when there are several steps因為那時候是好幾個步驟， and you do something as a precaution而如果只是多做一件小心的事， when there is one extra careful act你就會說 as a precaution。

It is not the same as a warning. A caution is often the words “be careful”; a precaution is the thing you actually do.

It is not the same as a warning.這跟 warning（警告）不一樣。A cautioncaution is often the words “be careful”常常就是「小心」這句話本身； a precautionprecaution is the thing you actually do則是你真正去做的那件事。

There is a rather old, uncommon verb to precaution, meaning to warn or arm someone ahead of time; almost nobody needs it now. The everyday grammar is the noun, with take and as a.

There is a rather old, uncommon verb to precaution有一個相當舊、不常見的動詞 to precaution， meaning to warn or arm someone ahead of time意思是事先警告或武裝某人； almost nobody needs it now現在幾乎沒有人會用到它。The everyday grammar is the noun日常用的文法是名詞形式， with take and as a搭配 take 或 as a 使用。