Valid

You ought to think over whether the premise is valid or not.

The ticket is valid for a week.

The ticket is valid to April 29.

This is a valid point of view.

This ticket is valid for three months.

How long is this visa valid?

This passport is valid for five years.

I had a valid visa, so I was allowed to enter the country.

Is it valid to say that all men are created equal?

His theory is widely accepted as valid.

I will believe him as soon as he offers a valid answer.

Few concepts are as emotionally charged as that of race. The word conjures up a mixture of associations—culture, ethnicity, genetics, subjugation, exclusion and persecution. But is the tragic history of efforts to define groups of people by race really a matter of the misuse of science, the abuse of a valid biological concept?

A valid format for the date is DD/MM/YY.

Do not drive without a valid license.

An argument is valid if and only if the set consisting of both (1) all of its premises and (2) the contradictory of its conclusion is inconsistent.