def split_string(tokens):
    result = []
    done = 1
    while(len(tokens) > 10 and done):
        done = 0
        for i in range(10, len(tokens), 1):
            if i > 30 :
                if tokens[i] in [".", "。", "!", "！", "?", "？", ",", "，", "……"]:
                    result.append(tokens[:i+1])
                    tokens = tokens[i+1:]
                    done = 1
                    break
            else :
                if tokens[i] in [".", "。", "!", "！", "?","？"] :
                    result.append(tokens[:i+1])
                    tokens = tokens[i+1:]
                    done = 1
                    break
    if len(tokens) > 0 :
        result.append(tokens)
    return result