valid duration造句

1、Please enter a valid duration. Example: For 1 hour 30 minutes enter 0130 or 130

2、Revising, writing or assisting in writing teaching materials without demanding any financial request during the valid duration of this contract.

3、If the valid duration of the patent right expires or the patent right is declared invalid, the patentee may not conclude a patent exploitation license contract relating to that patent with others.