'I cooked it myself, so be careful!' he joked.

“我亲自下厨做的，所以要小心点哟！”他开玩笑说。

《牛津词典》

So be careful whenever a company says its product is "the most popular".

所以，当一家公司说它的产品是“最受欢迎的”时，一定要小心。

youdao

So be careful.

一定要小心！

youdao

So it looks like what is supposed to be a simple enumeration or careful count of the nation's population this year will be anything but routine.

VOA: standard.2010.02.03

So it's a way of reminding you, I've got to be careful about the types of things that I put in.

因此我这是在提醒你，一定要对输入的东西的类型,多加注意。

麻省理工公开课 - 计算机科学及编程导论课程节选

So, that kind of stuff is something to look at but I'd be very careful in buying equities.

所以这样的投资工具就是我们所要考虑的,但我对资产板块的投资会比较小心。

耶鲁公开课 - 金融市场课程节选

Bottom line: your phone has lots of valuable data on it, so be careful with it.

FORBES: The Department of Homeland Security Wants You To Be More Careful With Your Phone

By the way, that is a 20 megabyte download so be careful there.

BBC: Apollo Lunar Surface Journal

In the meantime, your employer is watching, so be careful what you say.

FORBES: Magazine Article