diff --git a/README.md b/README.md
index 9fb843e..6fdc393 100644
--- a/README.md
+++ b/README.md
@@ -214,6 +214,7 @@ options:
   --keep-frames                                            keep temporary frames
   --many-faces                                             process every face
   --map-faces                                              map source target faces
+  --mouth-mask                                             mask the mouth region
   --nsfw-filter                                            filter the NSFW image or video
   --video-encoder {libx264,libx265,libvpx-vp9}             adjust output video encoder
   --video-quality [0-51]                                   adjust output video quality
diff --git a/modules/core.py b/modules/core.py
index acbbbe4..ee67402 100644
--- a/modules/core.py
+++ b/modules/core.py
@@ -41,7 +41,7 @@ def parse_args() -> None:
     program.add_argument('--many-faces', help='process every face', dest='many_faces', action='store_true', default=False)
     program.add_argument('--nsfw-filter', help='filter the NSFW image or video', dest='nsfw_filter', action='store_true', default=False)
     program.add_argument('--map-faces', help='map source target faces', dest='map_faces', action='store_true', default=False)
-    program.add_argument('--mouth-mask', help='mouth mask', dest='mouth_mask', action='store_true', default=False)
+    program.add_argument('--mouth-mask', help='mask the mouth region', dest='mouth_mask', action='store_true', default=False)
     program.add_argument('--video-encoder', help='adjust output video encoder', dest='video_encoder', default='libx264', choices=['libx264', 'libx265', 'libvpx-vp9'])
     program.add_argument('--video-quality', help='adjust output video quality', dest='video_quality', type=int, default=18, choices=range(52), metavar='[0-51]')
     program.add_argument('--live-mirror', help='The live camera display as you see it in the front-facing camera frame', dest='live_mirror', action='store_true', default=False)