Hi Barbara Zobrist , 

What you are seeing is expected behavior with the Multilingual Excel File Type. When Import Multilingual Translations (Excel) is run, Studio can safely segment only the source. It cannot reliably determine how the existing translation in the target cell should be segmented, because the target may contain a different number of sentences or a different sentence structure. (community.rws.com)

For that reason, the import task deliberately places the entire target-cell content into the first segment of the paragraph rather than trying to distribute it automatically across all split segments. This was done as the safer option, to avoid incorrect alignment and duplicated or misplaced content in the exported file. (community.rws.com)

So unfortunately there is no automatic way to correctly associate one multi-sentence translation cell with multiple source segments during import. In these cases, a manual post-edit/review is needed so you can split or move the imported translation to the correct segments yourself. (community.rws.com)

Hi Patrick Andrew Hartnett ,
Thank you for your reply! I thought maybe there is a solution that Excel segments the source by entire cells, and not by sentence.
But anyway, thank you very much for your answer :)