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README.md

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 ## Introduction
 
-Qwen1.5 is a transformer-based decoder-only language model pretrained on a large amount of data. In comparison with the previous released Qwen, the improvements include: 
+Qwen1.5 is the beta version of Qwen2, a transformer-based decoder-only language model pretrained on a large amount of data. In comparison with the previous released Qwen, the improvements include: 
 
 * 6 model sizes, including 0.5B, 1.8B, 4B, 7B, 14B, and 72B;
 * Significant performance improvement in human preference for chat models;