diff --git a/src/interface.jl b/src/interface.jl
index 96cc99e..a1afdd5 100644
--- a/src/interface.jl
+++ b/src/interface.jl
@@ -78,8 +78,8 @@ function removeLatestMsg(a::agent)
   end
 end
 
-function generatePrompt(a::agent; 
-                      userToken::String=" [/INST]", assistantToken=" [INST]", 
+function generatePrompt_tokenSuffix(a::agent; 
+                      userToken::String="[/INST]", assistantToken="[INST]", 
                       systemToken="[INST]<<SYS>> content <</SYS>>")
   prompt = nothing
   for msg in a.messages
@@ -100,6 +100,28 @@ function generatePrompt(a::agent;
   return prompt
 end
 
+function generatePrompt_tokenPrefix(a::agent; 
+                      userToken::String=" [/INST]", assistantToken=" [INST]", 
+                      systemToken="[INST]<<SYS>> content <</SYS>>")
+  prompt = nothing
+  for msg in a.messages
+    role = msg[:role]
+    content = msg[:content]
+
+    if role == "system"
+      prompt = replace(systemToken, "content" => content)
+    elseif role == "user"
+      prompt *= userToken * content * " "
+    elseif role == "assistant"
+      prompt *= assistantToken * content * " "
+    else
+      error("undefied condition role = $role")
+    end
+  end
+
+  return prompt
+end
+
 
 
 
@@ -154,7 +176,6 @@ end
 
 
 
-
 
 
 end # module
\ No newline at end of file