diff --git a/inference.py b/inference.py
index a0b00790..9349c603 100644
--- a/inference.py
+++ b/inference.py
@@ -106,7 +106,7 @@ def main(args):
     parser.add_argument("--pose_style", type=int, default=0,  help="input pose style from [0, 46)")
     parser.add_argument("--batch_size", type=int, default=2,  help="the batch size of facerender")
     parser.add_argument("--size", type=int, default=256,  help="the image size of the facerender")
-    parser.add_argument("--expression_scale", type=float, default=1.,  help="the batch size of facerender")
+    parser.add_argument("--expression_scale", type=float, default=1.,  help="A larger value will make the expression motion stronger.")
     parser.add_argument('--input_yaw', nargs='+', type=int, default=None, help="the input yaw degree of the user ")
     parser.add_argument('--input_pitch', nargs='+', type=int, default=None, help="the input pitch degree of the user")
     parser.add_argument('--input_roll', nargs='+', type=int, default=None, help="the input roll degree of the user")