checkpoint data set

例句：

1. 1. The checkpoint was a crucial moment for the team to gather information.
   检查点是团队收集信息的关键时刻。
2. 2.The soldiers had to pass through several checkpoint points on their way to the front.
   士兵们在前往前线的路上必须经过几个检查点。
3. 3. During the war, checkpoints were used to prevent enemy spies from infiltrating the country.
   在战争中，检查点被用来防止敌人间谍渗透国家。