I am using an app called Duolingo to practice learning German through assimilation techniques however I have come across something that is a bit confusing to me in a a way, regarding the way that words should be placed. In the following example you will see what I am talking about:
Translate Into German
The dog is strong although he is old.
I end up putting in:
Der Hund ist stark, obwohl er ist alt.
However the actual translation that they are looking for is:
Der Hund ist stark, obwohl er alt ist.
Would anyone know the proper rules for this so I can I figure out why this is and when? Thanks!