Dàizi shàng de móguǐzhān yòng jiù le, nián búzhù le.
The Velcro on the bag is worn out - it doesn't stick anymore.
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Taiwan term ('devil felt' - because of how stubbornly it grips). Mainland China uses 魔术贴 (móshùtiē, 'magic stick') for the same thing. Both are everyday words; brand-name 'Velcro' isn't used in Chinese.
