Explain only what you have witnessed. All other information about an event must be sourced unless you are certain of your information.

除了摄影记者亲身见证的信息，图片说明中的其他任何信息必须标明来源。

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Although Stark International is a U.S. firm, vibranium must be sourced in the African nation of Wakanda.

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Almost every job must be sourced locally.

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