以防的用法和樣例：
例句
-
他們在窗戶上加了窗條以防盜賊進入。
They fitted bars to their windows to stop burglars getting in. -
可能下雨--你最好帶把傘，以防萬一（下起來）。
It may rain you'd better take an umbrella (just) in case (it does). -
我已籌備了一筆準備基金以防不測。
I have kept a reserve fund in case of accidents. -
我把一切東西都鎖在保險箱里以防萬一。
I took the precaution of locking everything in the safe. -
我們應該使用無煙煤以防止空氣污染。
We should use anthracite to avoid air pollution.
