diff --git a/deepspeech/modules/encoder.py b/deepspeech/modules/encoder.py
index a9b5e8a6..0f8f1075 100644
--- a/deepspeech/modules/encoder.py
+++ b/deepspeech/modules/encoder.py
@@ -383,7 +383,7 @@ class TransformerEncoder(BaseEncoder):
         """Encode input frame.
 
         Args:
-            xs (paddle.Tensor): Input tensor. (B, T, D)
+            xs (paddle.Tensor): (Prefix) Input tensor. (B, T, D)
             masks (paddle.Tensor): Mask tensor. (B, T, T)
             cache (List[paddle.Tensor]): List of cache tensors.
 
@@ -396,7 +396,6 @@ class TransformerEncoder(BaseEncoder):
             xs = self.global_cmvn(xs)
 
         if isinstance(self.embed, Conv2dSubsampling):
-            # xs, masks = self.embed(xs, masks)
             #TODO(Hui Zhang): self.embed(xs, masks, offset=0), stride_slice not support bool tensor
             xs, pos_emb, masks = self.embed(xs, masks.astype(xs.dtype), offset=0)
         else: