Learn Hardcore Danish: Tiden går hurtigt, når vi arbejder i haven. - Time goes quickly when we work in the garden.

Danish often uses går in expressions about how time "goes" or "passes." So Tiden går hurtigt literally means "Time goes quickly," which is the natural way to say "Time passes quickly" in Danish.

What part of speech is hurtigt, and why is it used here instead of hurtig?

Hurtigt is an adverb, modifying the verb går to describe how time passes. Hurtig is the adjective form, which would be used to describe a noun (for example, en hurtig bil, "a fast car").

Why is i haven used, not på haven or something else?

In Danish, i is typically used to mean "in" or "within" a space (like a garden, room, or building). So i haven is "in the garden." Meanwhile, på often means "on" or is used with certain idiomatic fixed expressions (such as på arbejde, "at work"), which do not apply here.

What is the significance of vi instead of os for "we" in this sentence?

In Danish, vi is the subject form ("we"), while os is the object form ("us"). Here, vi is the subject performing the action of working, so vi is required.

Does når in når vi arbejder i haven mean "when" in a temporal sense, a conditional sense, or both?

In Danish, når generally means "when" in a temporal sense, referring to a regular or repeated occurrence. It can sometimes carry a conditional feel (like "if" or "whenever"), but in this context, it simply means "time goes quickly whenever/each time we work in the garden."