diff --git a/grammars/testConversions/MicroAbs.gf b/grammars/testConversions/MicroAbs.gf
new file mode 100644
index 000000000..44a3a0982
--- /dev/null
+++ b/grammars/testConversions/MicroAbs.gf
@@ -0,0 +1,8 @@
+
+abstract MicroAbs = {
+
+cat S;
+
+fun vars : S;
+
+}
diff --git a/grammars/testConversions/MicroCnc.gf b/grammars/testConversions/MicroCnc.gf
new file mode 100644
index 000000000..c58c44c9b
--- /dev/null
+++ b/grammars/testConversions/MicroCnc.gf
@@ -0,0 +1,10 @@
+
+concrete MicroCnc of MicroAbs = {
+
+lincat S = {a : {s1:Str ; s2:Str}};
+
+lin vars = {a = variants { {s1="a" ; s2=variants{"b";"c"}} ; {s1="d";s2="e"} }};
+
+}
+
+
diff --git a/src/GF/UseGrammar/Custom.hs b/src/GF/UseGrammar/Custom.hs
index 03e66837d..66ba55934 100644
--- a/src/GF/UseGrammar/Custom.hs
+++ b/src/GF/UseGrammar/Custom.hs
@@ -169,6 +169,7 @@ customGrammarPrinter =
 -- grammar conversions, (peb) 
   ,(strCI "gfc_show",   show . grammar2canon . stateGrammarST)
   ,(strCI "gfc_raw",    prRaw . stateGrammarST)
+  ,(strCI "tnf",        prCanon . convertCanonToTNF . stateGrammarST)
   ,(strCI "mcfg",       prMCFG . convertCanonToMCFG . stateGrammarST)
   ,(strCI "mcfg_cf",    prCF . convertCanonToCF . stateGrammarST)
   ,(strCI "mcfg_canon", prCanon . convertCanonToMCFG . stateGrammarST)