Learn Icelandic: Keyr hægt og varlega! - Drive slowly and carefully!

To give a command to one person in Icelandic, you usually just take the infinitive or dictionary form of the verb (here, keyra, meaning "to drive") and drop the final -a. That leaves us with the imperative form keyr.

Why is there no word for "you" in this sentence?

Just like in English, Icelandic commands usually leave out the word for "you" (þú). You just use the command form of the verb (keyr) by itself to tell someone what to do. Note that in casual speech, Icelanders often attach "you" to the end of the verb instead, which would make it keyrðu.

I've seen hægt used as the neuter word for "slow". Why is it used here to mean "slowly"?

In Icelandic, the neuter singular form of an adjective is very frequently used as an adverb. The standard adjective for "slow" is hægur, its neuter form is hægt, and we use hægt here to describe how the driving is done: "slowly".

Does the -lega ending on varlega work like "-ly" in English?

Yes, it does! The suffix -lega is a very common way to turn an adjective into an adverb in Icelandic. Here, it takes the root of the adjective var (cautious or aware) and turns it into the adverb varlega (carefully or cautiously).