如需利用现有内容提高营销效率，可采用哪两种方法？

The correct options, "Repurpose social media posts with good engagement from other platforms" and "Break down a research report into several infographics," both describe effective strategies for content repurposing. Repurposing existing, high-performing content saves time and resources while extending its reach and value. Repackaging content into new formats (like infographics from a report) or sharing successful content across platforms maximizes its impact. "Research and write an article" is content creation, not repurposing. "Do not reuse content because it will become outdated" is incorrect; content can often be updated or repurposed to remain relevant.