In V & V model , every phase is in association with testing part.
In requirement analysis, it is made sure that every requirement is collected and is discussed with clients for requirement analysis and later it is verified and validated.
After requirement analysis, next phase is high level design after the collection of requirements the developers will do design at high level.
Next phase is low level design here the design is done at low level.
After the low level design comes the coding, here the programmers based on the functionalities and requirements will do coding.
Once the coding is done, it is passed on to unit testing.
After it has undergone unit testing then next phase is integration testing. Here multiple modules are clubbed together to do integration testing. It is done based on high level design document.
Next phase is system testing, here it is made sure that the complete functionality is being implemented as per the requirements stated before.