加法练习，程序会随机给出两个两位数，在规定时间内进行作答，如果回答错误，或者是时间到达，认为回答错误，累计十次计算后，给予结果-Addition to practice, procedures will be randomly given two double-digit in the specified time to answer the question, if answered wrong, or the time taken to reach that answer wrong, a