You really must have your wits about your when dealing with such people.

跟这类人打交道，你必须格外警觉。

That's a practicable course of action.

那是一个切合实际的行动方案。

Keep to the rules, and nothing can go wrong.

按规矩办事情就不会出差子。

Rome wasn't built in a day.

罗马不是一天建成的。

What does that mean in plain English?

你能不能用大白话解释一下？

Were you raised in a bam?

你是牲口棚里长大的吗？