Learn Farsi: خواهش می‌کنم، صبر کن.

The literal translation of خواهش می‌کنم is "I make a request". If you say it after someone thanks you, it acts like "you're welcome". But when you say it before asking someone to do something, like in this sentence, it translates to "please".

What is the literal translation of صبر کن?

In Farsi, many verbs are formed by combining a noun with a "helper" verb. صبر means "patience" and کن is the command form of "to do". So you are literally telling someone to "do patience"!

Why doesn't the command کن start with the prefix بـ (be-) like other commands I've learned?

While many command verbs start with بـ (for example, برو meaning "go"), compound verbs that use "to do" (کردن) are an exception. For these, the command form is simply کن without the prefix.

Is صبر کن polite enough to use with a stranger?

صبر کن is the informal, singular form, so it is best used with friends, family, or children. If you are speaking to a stranger, someone older, or a group of people, you should use the formal version صبر کنید instead.