Dot does not always mean end of sentence.
There's a problem with one of the immersion items called Información General. Close to the top, a sentence ends with "40.000 km." This means that Duolingo assumes the next word is the beginning of a new sentence. When translated, neither "sentence" makes sense. I don't know how to fix this in proofread other than to type in two botched groups of words.
I haven't done much Immersion work but have noticed it in the German articles as well. The one example I can find is in the Wikipedia article on Manfred von Richtofen I uploaded.
"Nach dem Besuch der Kadettenanstalt Wahlstatt trat er im Frühjahr 1911 als Fähnrich in das Ulanen-Regiment „Kaiser Alexander III. von Rußland“ (Westpreußisches) Nr. 1 in Militsch ein."
... which is broken into two sentences because of the period after Kaiser Alexander III.