One of those separable verbs, it seems: wiederkommen, meaning to come back or recur.
Do the separable verb parts always have to go at the end of the sentence?
Yes it's because of the dative case. A lot of nouns take an ending "n" with dative.
I think this sentence uses the German imperative, being a polite command rather than a question.
Hypothetical situation: A man called Bob goes to a shop to buy some shoes which are very popular and are selling out quickly. When Bob asks the sales assistant for a pair of these shoes he is told, "There are currently none in stock due to their popularity however there will be a new delivery of these shoes in the next three days." The sales assistant then says, "Kommen Sie bitte in drei Tagen wieder" - "Please come back in three days".
I think you're right. Looks to me, no expert, that this is imperative with bitte to be polite as you say, and the weider, again, not a seperable verb as suggested in earlier posts. But input from a mod would help clear this up. :)
Thanks, I lingotted you :)
'Bitte kommen weider in drei Tagen'. How is it? Not good? If so, why? What else?
You would be understood - but for "Kommen Sie wieder" English-speakers would say "Come back again", and then add the time period. We do sometimes separate bits of verbal phrases, but not in this example!
But come back is not accepted ! If you come back isn't the here understood?
I think it would be wrong because "in three days" means three days from now whereas "after three days means any time after three days have passed.
The female voice seems to be saying "winder" instead of "wieder".