diff --git a/userspace/tiny.c b/userspace/tiny.c
index e475780..52f11a8 100644
--- a/userspace/tiny.c
+++ b/userspace/tiny.c
@@ -284,6 +284,23 @@ void run()
 
 int func_tiny()
 {
+    printf("TinyC grammar\n");
+    printf("<program> ::= <statement>\n");
+    printf("<statement> ::= \"if\" <paren_expr> <statement> |\n");
+    printf("                \"if\" <paren_expr> <statement> \"else\" <statement> |\n");
+    printf("                \"while\" <paren_expr> <statement> |\n");
+    printf("                \"do\" <statement> \"while\" <paren_expr> \";\" |\n");
+    printf("                \"{\" { <statement> } \"}\" |\n");
+    printf("                <expr> \";\" |\n");
+    printf("                \";\"\n");
+    printf("<paren_expr> ::= \"(\" <expr> \")\"\n");
+    printf("<expr> ::= <test> | <id> \"=\" <expr>\n");
+    printf("<test> ::= <sum> | <sum> \"<\" <sum> | <sum> \">\" <sum>\n");
+    printf("<sum> ::= <term> | <sum> \"+\" <term> | <sum> \"-\" <term>\n");
+    printf("<term> ::= <id> | <int> | <paren_expr>\n");
+    printf("<id> ::= \"a\" | \"b\" | \"c\" | \"d\" | ... | \"z\"\n");
+    printf("<int> ::= <an_unsigned_decimal_integer>\n");
+
     int i;
     ch      = ' ';
     sym     = 0;