There isn't an automatic way to do this, but here are a couple of
options I can think of:
1) Create your wordle with German words removed and then manually
remove the English words by right clicking on each of them one by one.
2) a) create your wordle with German common words removed
b) copy and paste to save the word list (under Language>word count)
c) create your wordle again this time with English words removed
d) copy and paste to save that word list
e) use a spreadsheet or text processor to generate the
intersection of the 2 lists
f) feed that list back into wordle advanced in the proper format
to create your final wordle.
If you go with method 2, here are some resources that may be helpful
Best of luck with your thesis!
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