Pseudo Code
参考答案：伪代码，又称虚拟代码，是高层次描述算法的一种。
现有质量相同的铁、铅（Pb）、铝三块金属，含原子数由少到多顺序排列的是： [ ]
A. 铅. 铁. 铝
B. 铁. 铅. 铝
C. 铝. 铁. 铅
D. 铁. 铝. 铅
You________all those clothes！We have a washing machine to do that sort of thing.[ ]
A. needn’t have washed
B. shouldn’t have washed
C. must not have washed
D. can not have washed
