Other restrictions include whether the user needs permission to transfer the content, in what format the content must be, and who the target audience is.

其他的限制还有：用户是否需要得到权限才能传递内容、内容的格式有何要求以及目标受众是谁。

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Include long-tail keyword phrases that really target terms that your prime target audience may use to search for your product or service online.

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