def present_active_subjunctive(self):
        """
        Weak verbs
        I
        >>> verb = WeakOldNorseVerb()
        >>> verb.set_canonic_forms(["kalla", "kallaði", "kallaðinn"])
        >>> verb.present_active_subjunctive()
        ['kalla', 'kallir', 'kalli', 'kallim', 'kallið', 'kalli']

        II
        >>> verb = WeakOldNorseVerb()
        >>> verb.set_canonic_forms(["mæla", "mælti", "mæltr"])
        >>> verb.present_active_subjunctive()
        ['mæla', 'mælir', 'mæli', 'mælim', 'mælið', 'mæli']

        III
        >>> verb = WeakOldNorseVerb()
        >>> verb.set_canonic_forms(["telja", "taldi", "talinn"])
        >>> verb.present_active_subjunctive()
        ['telja', 'telir', 'teli', 'telim', 'telið', 'teli']

        IV
        >>> verb = WeakOldNorseVerb()
        >>> verb.set_canonic_forms(["vaka", "vakta", "vakat"])
        >>> verb.present_active_subjunctive()
        ['vaka', 'vakir', 'vaki', 'vakim', 'vakið', 'vaki']

        :return:
        """
        subjunctive_root = self.sng[:-1] if self.sng[-1] == "a" else self.sng
        forms = [subjunctive_root + "a"]

        subjunctive_root = subjunctive_root[:-1] if subjunctive_root[-1] == "j" else subjunctive_root
        forms.append(subjunctive_root+"ir")
        forms.append(subjunctive_root+"i")
        forms.append(subjunctive_root+"im")
        forms.append(subjunctive_root+"ið")
        forms.append(subjunctive_root+"i")
        return forms