完善 README 中关于加载已有模型的说明

README.md

@@ -219,8 +219,13 @@ pip install -r requirements.txt -i https://pypi.tuna.tsinghua.edu.cn/simple
 
 ```bash
 git clone https://huggingface.co/jingyaogong/MiniMind2
+cd MiniMind2
+git lfs install
+git lfs pull
 ```
 
+**重要**：完成上面指令后，移动 MiniMind2 目录到 minimind 的根目录下，否则执行下面的步骤会找不到模型。
+
 ### 3.命令行问答
 
 ```bash

README_en.md

@@ -233,8 +233,13 @@ pip install -r requirements.txt -i https://pypi.tuna.tsinghua.edu.cn/simple
 
 ```bash
 git clone https://huggingface.co/jingyaogong/MiniMind2
+cd MiniMind2
+git lfs install
+git lfs pull
 ```
 
+**Important**: After completing the above instructions, move the MiniMind2 directory to the root directory of minimind. Otherwise, the model won't be found when you execute the following steps.
+
 ### 3. Command-line Q&A
 
 ```bash