Answers

Jul 10, 2017 - 10:58 AM
Hello, here it's a different situation as when you need to use the verb in the infinitive
The second verb goes at the end of a sentence in infinitive form only when it's linked to the first verb and has the same subject, as in:
Ich möchte arbeiten/I want to work, Ich muss arbeiten/I have to work, etc
That's the kind of sentences we've mostly used so far, yet in this example, the structure is a bit more complex. The second verb is not directly linked to the first one, and it has another subject "eure Schwester", (it's like an inner clause within the main one) so here the verb has to be conjugated, just like in English actually: I think your sister works in Köln (and not "to work")
You'll work more and more on these structures with verbs like "denken", "sagen" etc as you move through the higher levels. Keep it up!
The second verb goes at the end of a sentence in infinitive form only when it's linked to the first verb and has the same subject, as in:
Ich möchte arbeiten/I want to work, Ich muss arbeiten/I have to work, etc
That's the kind of sentences we've mostly used so far, yet in this example, the structure is a bit more complex. The second verb is not directly linked to the first one, and it has another subject "eure Schwester", (it's like an inner clause within the main one) so here the verb has to be conjugated, just like in English actually: I think your sister works in Köln (and not "to work")
You'll work more and more on these structures with verbs like "denken", "sagen" etc as you move through the higher levels. Keep it up!

Jul 11, 2017 - 07:42 AM
Thanks for the explanation! It was a bit surprising to see that structure without any lesson explaining it.