向毛主席保证： https://www.canada.ca/content/dam/ircc/migration/ircc/english/resources/manuals/enf/enf04-eng.pdf
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13.18 Valid visas in expired passports Visa officers will not put a visa in an expired document and will not issue a visa for a period surpassing the expiry date of the passport or travel document. Occasionally, documents containing valid visas are cancelled or replaced. If a valid visa inside an expired document is ENF 4 Port of entry examinations 2019-02-01 74 presented at the POE along with a valid passport or travel document, the visa is considered valid.