Imperfect Subjunctive of German verb hineintappen

The conjugation of hineintappen (stumble in, tread in cautiously) in subjunctive II is: ich tappte hinein, du tapptest hinein, er tappte hinein, wir tappten hinein, ihr tapptet hinein, sie tappten hinein. As a regular verb the unmodified stem tapp is used. The subjunctive endings -te, -test, -te, -ten, -tet, -ten are appended to this stem. The prefix hinein- of hineintappen is separated. The conjugation of these forms conforms to the grammatical rules for verbs in the subjunctive II tense.