1. 無疑的：不疑 doubt not; | 無疑的 doubtlessly; | 可疑 suspicious, questionable;

2. 无疑地;肯定地：dosed 服药;剂量 | doubtlessly 无疑地;肯定地 | downright 明显的;全然;完全

adv

1. without doubt
    certainly

    e.g. it's undoubtedly very beautiful

    Synonym: undoubtedlydoubtless