sql query with variables .net VB

Hi,
Next problem with my first page. I have an sql query:

SELECT sprachen.sprache_@reftex4, uebgebiete.gebiet_@reftex4, referenz.id, referenz.kunde, sprachen_1.sprache_@reftex4 AS sprach1 FROM referenz INNER JOIN sprachen ON referenz.sprach2 = sprachen.id INNER JOIN uebgebiete ON referenz.gebiet = uebgebiete.id INNER JOIN sprachen AS sprachen_1 ON referenz.sprach1 = sprachen_1.id ORDER BY sprache_@reftex4, sprach1, gebiet_@reftex4
and get the error that column sprache_@reftex4 does not exist.
@reftex4 stands for a variable and after very long searches on the net I found that variables in .net are set with @ in an sql query. But I get an error for it.
@reftex4 could be de, en, fr, it, lu

Hint: Before (3 days ago) starting with .net I only programmed asp classic and there you could implement them easily with "&@reftex4&"
Thx for the help,
Pascal
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