diff --git a/example/tuling123-bot.js b/example/tuling123-bot.js
index 6929f04f96270906bcdc04b49037ca780c4425fd..c55763149090f0a5e6e30d7aece108ff314cbdb2 100644
--- a/example/tuling123-bot.js
+++ b/example/tuling123-bot.js
@@ -11,8 +11,9 @@
  *
  */
 const log = require('npmlog')
-const co = require('co')
+const co  = require('co')
 const Tuling123 = require('tuling123-client')
+const EventEmitter2 = require('eventemitter2')
 
 const Wechaty = require('../src/wechaty')
 //log.level = 'verbose'
@@ -56,17 +57,75 @@ bot.init()
   process.exit(-1)
 })
 
-function talk(m) {
-  co(function* () {
-    const fromId = m.from().id
-    const content = m.content()
-    const {code, text} = yield brain.ask(content, {userid: fromId})
+class Talker extends EventEmitter2 {
+  constructor(thinker) {
+    log.verbose('Talker()')
+    super()
+    this.thinker = thinker
+    this.obj = {
+      text: []
+      , time: []
+    }
+    this.timer = null
+  }
 
+  save(text) {
+    log.verbose('Talker', 'save(%s)', text)
+    this.obj.text.push(text)
+    this.obj.time.push(Date.now())
+  }
+  load() {
+    const text = this.obj.text.join(', ')
+    log.verbose('Talker', 'load(%s)', text)
+    this.obj.text = []
+    this.obj.time = []
+    return text
+  }
+  
+  updateTimer(delayTime) {
+    delayTime = delayTime || this.delayTime()
+    log.verbose('Talker', 'updateTimer(%s)', delayTime)
+    
+    if (this.timer) { clearTimeout(this.timer) }
+    this.timer = setTimeout(this.say.bind(this), delayTime)
+  }
+  
+  hear(text) {
+    log.verbose('Talker', `hear(${text})`)
+    this.save(text)
+    this.updateTimer()
+  }
+  say() {
+    log.verbose('Talker', 'say()')
+    const text  = this.load()
+    this.thinker(text)
+    .then(reply => this.emit('say', reply))
+    this.timer = null
+  }
+  
+  delayTime() {
     const minDelayTime = 5000
     const maxDelayTime = 15000
     const delayTime = Math.floor(Math.random() * (maxDelayTime - minDelayTime)) + minDelayTime
+    return delayTime
+  }
+}
 
-    log.info('Bot', `REPLY(after ${Math.floor(delayTime/1000)}s): {code:${code}, text:${text}}`)
-    setTimeout(r => { bot.reply(m, text) }, delayTime)
-  })
+var Talkers = []
+
+function talk(m) {
+    const fromId  = m.from().id
+    const groupId = m.group().id
+    const content = m.content()
+    
+    const talkerName = fromId + groupId
+    if (!Talkers[talkerName]) {
+      Talkers[talkerName] = new Talker(function(text) {
+        log.info('Tuling123', 'Talker is thinking how to reply: %s', text)
+        return brain.ask(text, {userid: talkerName})
+        .then(r => r.text)
+      })
+      Talkers[talkerName].on('say', reply => bot.reply(m, reply))
+    }
+    Talkers[talkerName].hear(content)
 }
diff --git a/package.json b/package.json
index 8748e805ec37093b57f974e32ea73456024c0858..d5f73081a5d6b5098753aa14dde22f841a6ec196 100644
--- a/package.json
+++ b/package.json
@@ -35,6 +35,7 @@
     "body-parser": "^1.15.0",
     "chromedriver": "^2.21.2",
     "co": "^4.6.0",
+    "eventemitter2": "^1.0.3",
     "express": "^4.13.4",
     "npmlog": "^2.0.3",
     "phantomjs-prebuilt": "^2.1.7",
diff --git a/src/contact.js b/src/contact.js
index 531c902f3ad66dca823a039a5075db6cadac5b5a..0d8c985118847763d80d545cb4110514a2f49432 100644
--- a/src/contact.js
+++ b/src/contact.js
@@ -10,19 +10,14 @@ const log = require('npmlog')
 
 class Contact {
   constructor(id) {
-    if (!Contact.puppet) {
-      throw new Error('no puppet attached to Contact')
-    }
     log.silly('Contact', `constructor(${id})`)
+    if (!Contact.puppet) { throw new Error('no puppet attached to Contact') }
 
     this.id = id
     this.obj = {}
   }
 
-  toString() {
-    var name = this.obj.name ? `${this.obj.name}@${this.id}` : this.id
-    return `Contact(${name})`
-  }
+  toString() { return `Contact(${this.obj.name}[${this.id}])` }
 
   parse(rawObj) {
     return !rawObj ? {} : {
diff --git a/src/group.js b/src/group.js
index ada15bda2d4df286a3beb9adce4b5702a4e16012..51249b66e170c1c07f3aea844083a7e963368be3 100644
--- a/src/group.js
+++ b/src/group.js
@@ -18,11 +18,7 @@ class Group {
       throw new Error('no puppet attached to Group')
     }
   }
-
-  toString()  {
-    var name = this.obj.name ? `[${this.obj.name}]${this.id}` : this.id
-    return `Group(${name})`
-  }
+  toString()  { return `Group(${this.obj.name}[${this.id}])` }
 
   ready(contactGetter) {
     log.silly('Group', `ready(${contactGetter})`)
diff --git a/src/message.js b/src/message.js
index abd050e367c828fdb19d373b7d6745acb686fde7..ee7229234e13e248630c5cb2de98d0a1f05cb134 100644
--- a/src/message.js
+++ b/src/message.js
@@ -70,6 +70,7 @@ class Message {
   group()   { return this.obj.group }
 
   ready() {
+    log.silly('Message', 'ready()')
     return this.obj.from.ready()    // Contact from
     .then(r => this.obj.to.ready()) // Contact to
     .then(r => this.obj.group && this.obj.group.ready())  // Group member list
diff --git a/src/puppet-web-browser.js b/src/puppet-web-browser.js
index 30f422fbcd96b427a8e78399d2511a938724f32c..31c01e3bb09a5ca4b1ad2590e2a1ffd9d5a44c4d 100644
--- a/src/puppet-web-browser.js
+++ b/src/puppet-web-browser.js
@@ -12,7 +12,6 @@ const fs        = require('fs')
 const path      = require('path')
 const WebDriver = require('selenium-webdriver')
 const log       = require('npmlog')
-//log.disableColor()
 
 class Browser {
   constructor(options) {
diff --git a/src/wechaty.js b/src/wechaty.js
index a43fbef69054878310e6fea2762116a247175a72..050a7a6334051a8385e17f8ae2497d6d516e8490 100644
--- a/src/wechaty.js
+++ b/src/wechaty.js
@@ -68,6 +68,10 @@ class Wechaty extends EventEmitter {
     return 'dong'
   }
 
+  /**
+   * @deprecated
+   * use on('scan', ({code, url}) => {}) instead.
+   */
   getLoginQrImgUrl() { return this.puppet.getLoginQrImgUrl() }
 }