1The company's invariable policy is to invest a portion of its profits in research and development.
2Is the speed of light invariable, or can it be affected by external factors?
3The invariable nature of the mathematical constant pi makes it a fundamental element in geometry.
4Try to maintain an invariable tone of voice when speaking to customers, regardless of their attitude.
5There is an invariable relationship between the amount of rainfall and the growth of crops in this region.