Duration: depending on your current level. If you are already on examination level, 10 teaching units may suffice to familiarize you with the testing format. If you stumm need to improve your level, you may need more (check how long does it take to reach the testing level). 檢定分級完全符合德語學習的進程，一般德文課程也都會按照上述分級，學生完成一階段德語課後，也會被德語老師鼓勵，去參... https://getdocumentschina.co/zai_xian_gou_mai_zheng_shu_/goethe-zertifikat-kaufen