diff --git a/egs/wsj/s5/utils/lang/extend_lang.sh b/egs/wsj/s5/utils/lang/extend_lang.sh
index 57f8e3d7588..7602cb983de 100755
--- a/egs/wsj/s5/utils/lang/extend_lang.sh
+++ b/egs/wsj/s5/utils/lang/extend_lang.sh
@@ -1,5 +1,6 @@
 #!/bin/bash
 # Copyright     2018  Johns Hopkins University (Author: Daniel Povey);
+#               2019  Dongji Gao
 
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,6 +19,7 @@
 
 # Begin configuration section.
 sil_prob=0.5
+silprob_file=
 # end configuration section
 
 echo "$0 $@"  # Print the command line for logging
@@ -43,6 +45,7 @@ if [ $# -ne 3 ]; then
   echo ""
   echo "Options"
   echo "     --sil-prob <probability of silence>             # default: 0.5 [must have 0 <= silprob < 1]"
+  echo "     --silprob-file <file contains silence probability>    # must be provided if lexicon is lexiconp_silprob.txt"
   exit 1;
 fi
 
@@ -52,6 +55,7 @@ dir=$3
 
 [ -f path.sh ] && . ./path.sh
 
+
 for f in $srcdir/phones.txt $lexicon; do
   if [ ! -f $f ]; then
     echo "$0: expected file $f to exist"
@@ -79,11 +83,26 @@ tmpdir=$dir/temp
 rm -r $tmpdir 2>/dev/null
 mkdir -p $tmpdir
 
-
-# TODO: more checking.
-if [ $(basename $lexicon) != lexiconp.txt ]; then
-  echo "$0: currently this script only supports the lexiconp.txt format; your lexicon"
-  echo " ... has to have that filename."
+silprob=false
+
+if [ $(basename $lexicon) == "lexiconp_silprob.txt" ]; then
+  silprob=true
+  if [ -z $silprob_file ] ; then
+    echo "silprob_file not provided, checking $srcdir"
+    if [ -f $srcdir/silprob.txt ]; then
+        silprob_file=$srcdir/silprob.txt
+        echo "silprob_file found in $srcdir"
+    else
+        echo "silprob_file not found in $srcdir" && exit 1;
+    fi
+  else
+    if [ ! -f $silprob_file ]; then
+      echo "$silprob_file does not exist" && exit 1;
+    fi
+  fi
+elif [ $(basename $lexicon) != lexiconp.txt ]; then
+  echo "$0: currently this script only supports the lexiconp.txt or lexiconp_silprob.txt format;"
+  echo " ... your lexicon has to have that filename."
 fi
 
 # Get the list of extra words.
@@ -105,22 +124,45 @@ fi
 
 if [ -f $dir/phones/word_boundary.txt ]; then
   # was `if $position_dependent_phones; then..` in prepare_lang.sh
-  # TODO: add support for silprobs
-  perl -ane '@A=split(" ",$_); $w = shift @A; $p = shift @A; @A>0||die;
-         if(@A==1) { print "$w $p $A[0]_S\n"; } else { print "$w $p $A[0]_B ";
+  if "$silprob"; then
+    perl -ane '@A=split(" ",$_); $w = shift @A; $p = shift @A; $silword_p = shift @A;
+              $wordsil_f = shift @A; $wordnonsil_f = shift @A; @A>0||die;
+         if(@A==1) { print "$w $p $silword_p $wordsil_f $wordnonsil_f $A[0]_S\n"; }
+         else { print "$w $p $silword_p $wordsil_f $wordnonsil_f $A[0]_B ";
          for($n=1;$n<@A-1;$n++) { print "$A[$n]_I "; } print "$A[$n]_E\n"; } ' \
-       < $lexicon > $tmpdir/lexiconp.txt || exit 1;
+         < $lexicon > $tmpdir/lexiconp_silprob.txt
+  else
+    perl -ane '@A=split(" ",$_); $w = shift @A; $p = shift @A; @A>0||die;
+           if(@A==1) { print "$w $p $A[0]_S\n"; } else { print "$w $p $A[0]_B ";
+           for($n=1;$n<@A-1;$n++) { print "$A[$n]_I "; } print "$A[$n]_E\n"; } ' \
+         < $lexicon > $tmpdir/lexiconp.txt || exit 1;
+  fi
 else
-  cp $lexicon $tmpdir/lexiconp.txt
+  if "$silprob"; then
+    cp $lexicon $tempdir/lexiconp_silprob.txt
+  else
+    cp $lexicon $tmpdir/lexiconp.txt
+  fi
 fi
 
 # Check that there are no unseen phones in the lexicon.
-if ! utils/sym2int.pl -f 3- $srcdir/phones.txt $tmpdir/lexiconp.txt >/dev/null; then
-  echo "$0: it looks like there are unseen phones in your lexicon $lexicon"
-  exit 1
+if "$silprob"; then
+  if ! utils/sym2int.pl -f 6- $srcdir/phones.txt $tmpdir/lexiconp_silprob.txt >/dev/null; then
+    echo "$0: it looks like there are unseen phones in your lexicon $lexicon"
+    exit 1
+  fi
+else 
+  if ! utils/sym2int.pl -f 3- $srcdir/phones.txt $tmpdir/lexiconp.txt >/dev/null; then
+    echo "$0: it looks like there are unseen phones in your lexicon $lexicon"
+    exit 1
+  fi
 fi
 
-ndisambig=$(utils/add_lex_disambig.pl --pron-probs $tmpdir/lexiconp.txt $tmpdir/lexiconp_disambig.txt)
+if "$silprob"; then
+  ndisambig=$(utils/add_lex_disambig.pl --pron-probs --sil-probs $tmpdir/lexiconp_silprob.txt $tmpdir/lexiconp_silprob_disambig.txt)
+else
+  ndisambig=$(utils/add_lex_disambig.pl --pron-probs $tmpdir/lexiconp.txt $tmpdir/lexiconp_disambig.txt)
+fi
 
 ndisambig=$[ndisambig+1]  # Add one to disambiguate silence.
 
@@ -146,6 +188,15 @@ silphone=`cat $srcdir/phones/optional_silence.txt` || exit 1;
     echo "but you may use the option --sil-prob 0.0 to stop it being used." ) && \
    exit 1;
 
+if "$silprob"; then
+  # remove the silprob
+  cat $tmpdir/lexiconp_silprob.txt |\
+    awk '{
+      for(i=1; i<=NF; i++) {
+        if(i!=3 && i!=4 && i!=5) printf("%s\t", $i); if(i==NF) print "";
+      }
+    }' > $tmpdir/lexiconp.txt
+fi
 
 # First remove pron-probs from the lexicon.
 perl -ape 's/(\S+\s+)\S+\s+(.+)/$1$2/;' <$tmpdir/lexiconp.txt >$tmpdir/align_lexicon.txt
@@ -161,7 +212,7 @@ if [ -f $dir/phones/nonterminals.txt ]; then
   for w in "#nonterm_begin" "#nonterm_end" $(cat $dir/phones/nonterminals.txt); do
     echo $w $w  # These are words without pronunciations, so leave those prons
                 # empty.
-  done >> $dir/phones/align_lexicon.txt
+    done >> $dir/phones/align_lexicon.txt
 fi
 
 # create phones/align_lexicon.int from phones/align_lexicon.txt
@@ -170,22 +221,39 @@ cat $dir/phones/align_lexicon.txt | utils/sym2int.pl -f 3- $dir/phones.txt | \
 
 # Create the basic L.fst without disambiguation symbols, for use
 # in training.
-
-utils/lang/make_lexicon_fst.py $grammar_opts --sil-prob=$sil_prob --sil-phone=$silphone \
-         $tmpdir/lexiconp.txt | \
-    fstcompile --isymbols=$dir/phones.txt --osymbols=$dir/words.txt \
-      --keep_isymbols=false --keep_osymbols=false | \
-    fstarcsort --sort_type=olabel > $dir/L.fst || exit 1;
+if "$silprob"; then
+  utils/lang/make_lexicon_fst_silprob.py $grammar_opts --sil-phone=$silphone \
+         $tmpdir/lexiconp_silprob.txt $silprob_file | \
+      fstcompile --isymbols=$dir/phones.txt --osymbols=$dir/words.txt \
+        --keep_isymbols=false --keep_osymbols=false |   \
+      fstarcsort --sort_type=olabel > $dir/L.fst || exit 1;
+else
+  utils/lang/make_lexicon_fst.py $grammar_opts --sil-prob=$sil_prob --sil-phone=$silphone \
+           $tmpdir/lexiconp.txt | \
+      fstcompile --isymbols=$dir/phones.txt --osymbols=$dir/words.txt \
+        --keep_isymbols=false --keep_osymbols=false | \
+      fstarcsort --sort_type=olabel > $dir/L.fst || exit 1;
+fi
 
 
 # and create the version that has disambiguation symbols.
-utils/lang/make_lexicon_fst.py $grammar_opts \
-  --sil-prob=$sil_prob --sil-phone=$silphone --sil-disambig='#'$ndisambig \
-     $tmpdir/lexiconp_disambig.txt | \
-   fstcompile --isymbols=$dir/phones.txt --osymbols=$dir/words.txt \
-              --keep_isymbols=false --keep_osymbols=false | \
-   fstaddselfloops $dir/phones/wdisambig_phones.int $dir/phones/wdisambig_words.int | \
-   fstarcsort --sort_type=olabel > $dir/L_disambig.fst || exit 1;
+if "$silprob"; then
+  utils/lang/make_lexicon_fst_silprob.py $grammar_opts \
+    --sil-phone=$silphone --sil-disambig='#'$ndisambig \
+    $tmpdir/lexiconp_silprob_disambig.txt $silprob_file | \
+    fstcompile --isymbols=$dir/phones.txt --osymbols=$dir/words.txt \
+      --keep_isymbols=false --keep_osymbols=false |   \
+    fstaddselfloops  $dir/phones/wdisambig_phones.int $dir/phones/wdisambig_words.int | \
+    fstarcsort --sort_type=olabel > $dir/L_disambig.fst || exit 1;
+else
+  utils/lang/make_lexicon_fst.py $grammar_opts \
+    --sil-prob=$sil_prob --sil-phone=$silphone --sil-disambig='#'$ndisambig \
+       $tmpdir/lexiconp_disambig.txt | \
+     fstcompile --isymbols=$dir/phones.txt --osymbols=$dir/words.txt \
+                --keep_isymbols=false --keep_osymbols=false | \
+     fstaddselfloops $dir/phones/wdisambig_phones.int $dir/phones/wdisambig_words.int | \
+     fstarcsort --sort_type=olabel > $dir/L_disambig.fst || exit 1;
+fi
 
 
 echo "$(basename $0): validating output directory"
diff --git a/egs/wsj/s5/utils/prepare_extended_lang.sh b/egs/wsj/s5/utils/prepare_extended_lang.sh
index 824654cabf1..57cfcaabe34 100755
--- a/egs/wsj/s5/utils/prepare_extended_lang.sh
+++ b/egs/wsj/s5/utils/prepare_extended_lang.sh
@@ -24,6 +24,7 @@ word_list= # if a word list (mapping words from the srcdict to IDs) is provided,
 # we'll make sure the IDs of these words are kept as before.
 # end configuration sections
 
+echo "$0: warning: This sript is is now deprecated. You may want to use utils/lang/extend_lang.sh"
 echo "$0 $@"  # Print the command line for logging
 
 . utils/parse_options.sh