If you have a lot
of stuff that's already been translated, you could import in some other way.
E.g. copy-paste the source and target texts side by side in excel, generate a tmx
and import it into your TM. Or just align the two texts and import the resulting TMX.
If you only need to import a couple dozen segments, copy-paste is the fastest way.
Hm...could you please describe it more closely, for us, new users?