diff --git a/doc/recognition.md b/doc/recognition.md
index 004487f92b972f728f7b093b31798a91b0ae0c56..45fa74ab80804c5988be6bdf0eb2f73f3c914292 100644
--- a/doc/recognition.md
+++ b/doc/recognition.md
@@ -209,7 +209,7 @@ infer_img: doc/imgs_words/en/word_1.png
 
 ```
 # 预测中文结果
-python3 tools/infer_rec.py -c configs/rec/rec_chinese_lite_train.yml -o Global.checkpoints={path/to/weights}/best_accuracy TestReader.infer_img=doc/imgs_words/ch/word_1.jpg
+python3 tools/infer_rec.py -c configs/rec/rec_chinese_lite_train.yml -o Global.checkpoints={path/to/weights}/best_accuracy Global.infer_img=doc/imgs_words/ch/word_1.jpg
 ```
 
 预测图片：
diff --git a/tools/program.py b/tools/program.py
index 18a4ab7dff8c7c8c9e1ab973c150266ca6815450..30e9d7379bd07a0570c613ea25d1b440ed8bc682 100755
--- a/tools/program.py
+++ b/tools/program.py
@@ -114,7 +114,7 @@ def merge_config(config):
                 global_config[key] = value
         else:
             sub_keys = key.split('.')
-            assert (sub_keys[0] in global_config)
+            assert (sub_keys[0] in global_config), "the sub_keys can only be one of global_config: {}, but get: {}, please check your running command".format(global_config.keys(), sub_keys[0])
             cur = global_config[sub_keys[0]]
             for idx, sub_key in enumerate(sub_keys[1:]):
                 assert (sub_key in cur)