You'd better be careful.

你要小心一点。

Did you hear the news?

你听说那条新闻了吗？

Those are the rules and regulations, and we have to abide by them.

这些就是这儿的规矩， 大家都应该遵守。

Please don't do it without asking.

未经允许请不要那么做。

Stop carrying the weight of the world on your shoulders.

别太操心了，没有你地球照样转。 （carry the weight of the world on one’s shoulders:自以为重任在肩。）

This place looks like a disaster area..

这地方简直像灾区。