additives of cement的用法和样例：
- The addition of cement or lime hardens the soil and greatly increases its compressive strength.
- Concrete is made of cement, sand, stone and water.
- The sack of cement hit the ground with a thump.
- Here is a Research of the pozzolanic activity by using the shaft-kiln calcined coal gangue and its result indicates that coal gangue can be used in great amount as addition of cement.
- What about the removal of cement sub-gingivally?