Chinese phrase
凭证有效期多久？ píng zhèng yǒu xiào qī duō jiǔ
Meaning
How long is the voucher valid?
When to use it
Asks how long a voucher remains valid. It is a polite way to ask about the time limit for using a voucher.
Example dialogue
请问，凭证有效期多久？ qǐng wèn píng zhèng yǒu xiào qī duō jiǔ
Excuse me, how long is the voucher valid?
这张凭证自出票日起有效90天。 zhè zhāng píng zhèng zì chū piào rì qǐ yǒu xiào 90 tiān
This voucher is valid for 90 days from the date of issue.