diff --git a/pkg/openai/session.py b/pkg/openai/session.py
index 633ec434..3e653701 100644
--- a/pkg/openai/session.py
+++ b/pkg/openai/session.py
@@ -73,8 +73,11 @@ class Session:
         self.last_interact_timestamp = int(time.time())
 
         # 向API请求补全
-        response = pkg.openai.manager.get_inst().request_completion(self.prompt, self.user_name + ':')
+        response = pkg.openai.manager.get_inst().request_completion(self.cut_out(self.prompt + self.user_name + ':' +
+                                                                                 text + '\n' + self.bot_name + ':',
+                                                                                 7, 1024), self.user_name + ':')
 
+        self.prompt += self.user_name + ':' + text + '\n' + self.bot_name + ':'
         # print(response)
         # 处理回复
         res_test = response["choices"][0]["text"]
@@ -94,6 +97,29 @@ class Session:
 
         return res_ans
 
+    # 截取prompt里不多于max_rounds个回合，长度为大于max_tokens的最小整数字符串
+    # 保证都是完整的对话
+    def cut_out(self, prompt: str, max_rounds: int, max_tokens: int) -> str:
+        # 分隔出每个回合
+        rounds_spt_by_user_name = prompt.split(self.user_name + ':')
+
+        result = ''
+
+        checked_rounds = 0
+        # 从后往前遍历，加到result前面，检查result是否符合要求
+        for i in range(len(rounds_spt_by_user_name) - 1, 0, -1):
+            result = self.user_name + ':' + rounds_spt_by_user_name[i] + result
+            checked_rounds += 1
+
+            if checked_rounds >= max_rounds:
+                break
+
+            if len(result) > max_tokens:
+                break
+
+        logging.debug('cut_out: {}'.format(result))
+        return result
+
     def persistence(self):
         if self.prompt == '':
             return