Examples
wǒ men我们zǒng shì总是yīng gāi应该dài shàng带上ān quán dài安全带yǐ fáng以防chū shì出事gù故。
我们总是应该带上安全带以防出事故。
We should always wear a seatbelt in case we have an accident.
以防下雨你最好带把伞。
You had better take an umbrella with you in case it rains.
带上你的外套以防下雨。
Take your coat in case it rains.