1. A threshold is set up in order to avoid too many unnecessary backtracks. 为了避免多次不必要回溯，回溯需要阈值的控制。
2. And if it backtracks from the promise, I want to say that this country is going to be in bad shape. 如果他们食言，我想说，这个国家的情况将会很糟糕。
3. When Jupiter backtracks and revisits Pisces, you could find that he is inspiring your more spiritual and compassionate side again. 当木星退步，并重新审视双鱼座，你会发现，他更是鼓舞人心的精神和慈善的一面了。
4. It takes processing time into account besides the deadline and resource requirement of the task sets in order to reduce scheduling backtracks and increase effectiveness. 该算法适用于可并行任务，并在考虑到了任务集的截止期和资源因素基础上，加入了运行时间因素，达到了减少调度返回次数以及提高有效性的目的。
5. But if the chosen option can't find a match or anything later in the regex fails, the regex backtracks to the last decision point where untried options remain and chooses one. 但是如果所选择的方案未能发现相应匹配，或者后来的匹配也失败了，正则表达式将回溯到最后一个决策点，然后在剩余的选项中选择一个。
