我在执行此代码时收到错误：

const now = new Date();
bot.on("guildMemberRemove", member => {
    console.log(member.user.username + ' left from a Server at ' +  now + `Just watch the logs on the server`)
  });

有什么帮助吗？:-) 问候，祝你有美好的一天！

编辑：

    const commando = require('discord.js-commando');
const bot = new commando.();
const now = new Date();
bot.registry.registerGroup('random', 'Random');
bot.registry.registerGroup('reply', 'Reply');
bot.registry.registerDefaults();
bot.registry.registerCommandsIn(__dirname + "/commands")
bot.on("ready", () => {
  console.log(`Bot has started, with ${bot.users.size} users, in ${bot.channels.size} channels of ${bot.guilds.size} guilds.`);
  bot.user.setActivity(`Serving ${bot.guilds.size} servers`);
});
bot.on("guildCreate", guild => {
  console.log(`New guild joined: ${guild.name} (id: ${guild.id}). This guild has ${guild.memberCount} members!`);
  bot.user.setActivity(`Serving ${bot.guilds.size} servers`);
});
bot.on("guildMemberRemove", member => {
    console.log(member.user.username + ' left from a Server at ' +  now + `Just watch the logs on the server ${guild.name}`)
  });
bot.on("message", async message => {
  var optionsGreetings = ["Hellouu", "Heyy", "Hi there", "How ya doing?", "LETS GO DUDE"];
  var optionsHowAreYou = ["I had a bad day, whats about you, how are you doing?", "Robots have no feelings but whats about you?", "I am pretty good!", "I am doing fine, thanks, and you?", "Im good, how are you?", ];
  var responseGreetings = optionsGreetings[Math.floor(Math.random()*optionsGreetings.length)];
  var responseHowAreYou = optionsHowAreYou[Math.floor(Math.random()*optionsHowAreYou.length)];
  //Hello responses
  if(message.content == 'Hello') {
    message.channel.send(responseGreetings)
  }
  if(message.content == 'Hi') {
    message.channel.send(responseGreetings)
  }
  if(message.content == 'Hey') {
    message.channel.send(responseGreetings)
  }
  //How Are you? Responses
  if(message.content == 'How are you?') {
    message.channel.send(responseHowAreYou)
  }
  if(message.content == 'ping') {
    message.reply(`API Latency is ${Math.round(bot.ping)}ms`)
  }
  if(message.content == 'why?') {
    message.channel.send(`Because!`)
  }
  if(message.content == 'why') {
    message.channel.send(`Because!`)
  }
  if(message.content == 'Why?') {
    message.channel.send(`Because!`)
  }
  if(message.content == 'Why') {
    message.channel.send(`Because!`)
  }
});
bot.login('MY_TOKEN')

里面可能有很多，但是，嘿，谁在乎呢？

我的错误，ocurs 是：referneceError：公会不是定义在...在...

吨的东西，我不能复制，我不想手动键入它，希望这可以帮助你理解我的 code！