def postag_str(postag_tuple):
    """
    postag_tuple 형태의 postag 를 postag_str 형으로 변경한다.abs

    Args :
        postag_tuple :  [word_1, pos_1, word_2, pos_2, ...]
    Returns :
        | 형태소1/pos1+형태소2/pos2
        | ex) "가/VV+다/EF"
    """
    postag_pair_list = []
    for postag_pair in postag_tuple:
        word = postag_pair[0]
        pos = postag_pair[1]
        postag_pair_list.append(word + "/" + pos)
    return "+".join(postag_pair_list)