例句與造句

1. Thus, the system of warranty of quality control of metal products  which allowed reducing the consumption of metal for the control of maintaining the level of quality  was created.
2. Under the new system _ which comes into force Jan . 1 _ diamonds will be traced from the mine to the jeweler's window via a " system of warranties ."
3. Under the new system, which comes into force Jan . 1, diamonds will be traced from the mine to the jeweler's window via a " system of warranties ."
4. It's difficult to find system of warranties in a sentence. 用system of warranties造句挺難的