standard lead

例句：

1. 1.The standard lead is used to measure the resistance of materials.
   标准铅用于测量材料电阻。
2. 2.The standard lead was used in the construction of the bridge.
   标准铅在桥梁建设中使用。
3. 3. The standard lead was used to make the circuit more reliable.
   标准铅被用来使电路更加可靠。