Learn Swedish: Hunden tappar kopplet och viftar på svansen. - The dog drops the leash and wags its tail.

In Swedish, you often use the preposition på when talking about moving or wiggling a body part. For example, a dog wags its tail (viftar på svansen), or a person nods their head (nickar på huvudet). If you left out på here, it would sound like the dog was holding a detached tail in its paws and waving it around like a flag!

Why does the Swedish sentence say svansen (the tail) instead of "its tail"?

When talking about body parts or personal items, Swedish usually just uses the definite form of the noun (here, svansen meaning "the tail") if it is obvious who it belongs to. Since the dog is the one wagging, we understand it is wagging its own tail, so a possessive word like sin or dess is not needed.

Does tappar mean "drops" or "loses"?

It means both! The verb tappar can mean accidentally dropping something physically, like the leash here, or losing something, like losing your keys (tappar nycklarna). Context tells us the dog dropped the leash.

How do we know the gender of the word for "leash" (koppel) from this sentence?

We can see that it is an ett word because of its definite ending. The dictionary form is ett koppel, and to say "the leash", we add -et to the end, making it kopplet.