Usages of duōjiǔ
你 认识 她 多久 了？nǐ rènshi tā duōjiǔ le?
How long have you known her?
他 为什么 还 没 来？ 我 需要 找 他。 你 等 了 多久？tā wèishénme hái méi lái? wǒ xūyào zhǎo tā. nǐ děng le duōjiǔ?
Why hasn’t he come yet? I need to look for him. How long have you been waiting?
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