SAT scores began dropping in 1963; today, on average, 30% of students do not complete high school in four years, a figure that rises to 50% in poor urban neighborhoods.
SAT 分数从1963年开始下降；今天，平均有30%的学生没有在四年内完成高中学业，这一数字在贫穷的城市社区达到了50%。
2
Figure 1 shows four storage servers that manage the storage provided by two disk subsystems.
图1显示了四个存储服务器，可管理由两个磁盘子系统提供的存储。
3
The process shown in Figure 1 requires four basic software components for the advanced registry system.