redundant degree of freedom

例句：

1. 1. The extra staff is a redundant expense.
   额外的员工是不必要的开支。
2. 2. Theprogram has been redundant since thenew system was implemented.
   自从实施了新系统，这个程序就变得多余了。
3. 3.Redundant systems can lead to inefficiency and waste.
   冗余系统会导致效率低下和浪费。