I am a German major, and I think your idea is a bit unrealistic. I want to reach CET-4 through half a year's study, unless: 1 you are very talented in language. You have basically not studied other professional knowledge in the past six months, but concentrated on learning German. If you can do it. The method is as follows: sign up for a German training class 1, and buy a book for junior to intermediate German in contemporary universities (1-3 volumes is enough), with clear grammar, or for non-professional students in new universities, and then buy a grammar book, analysis and connection of German grammar. 3 voice stage 1 month, read German for more than 2 hours every day. From the second week of learning German, I began to contact grammar, learning the neutrality of nouns, the valence of verbs, the usage of prepositions, and the inflections of articles and verbs. While attending the training class, I taught myself the textbooks I bought, listened and read more, and recited the texts. After studying for 4 or 5 months, I bought a vocabulary book and a CET-4 test and tried to do it.