diff --git a/xiaogpt/langchain/chain.py b/xiaogpt/langchain/chain.py
index a7ffe094..e9bcbd3e 100644
--- a/xiaogpt/langchain/chain.py
+++ b/xiaogpt/langchain/chain.py
@@ -2,8 +2,7 @@
 from langchain.agents import AgentType
 from langchain.tools import BaseTool
 from langchain.llms import OpenAI
-
-# from langchain.chains import LLMMathChain
+from langchain.chains import LLMMathChain
 from langchain.utilities import SerpAPIWrapper
 from langchain.chat_models import ChatOpenAI
 from langchain.memory import ChatMessageHistory
@@ -25,13 +24,13 @@ def agent_search(query):
 
     # Initialization: search chain, mathematical calculation chain, custom summary email chain
     search = SerpAPIWrapper()
-    # llm_math_chain = LLMMathChain.from_llm(llm=llm, verbose=False)
+    llm_math_chain = LLMMathChain.from_llm(llm=llm, verbose=False)
     mail_summary = MailSummaryTool()
 
     # Tool list: search, mathematical calculations, custom summary emails
     tools = [
         Tool(name="Search", func=search.run, description="如果你不知道或不确定答案，可以使用这个搜索引擎检索答案"),
-        # Tool(name="Calculator", func=llm_math_chain.run, description="在需要回答数学问题时非常有用"),
+        Tool(name="Calculator", func=llm_math_chain.run, description="在需要回答数学问题时非常有用"),
         Tool(
             name="MailSummary",
             func=mail_summary.run,