Twitter.configure do |config|
    config.consumer_key = auth_user_CONSUMER_KEY
    config.consumer_secret = auth_user_CONSUMER_SECRET
    config.oauth_token = auth_user_OAUTH_TOKEN
    config.oauth_token_secret = auth_user_OAUTH_TOKEN_SECRET
  end

  Twitter.retweet(tweet_id)

  # Here, tweet_id is an ID of an existing status to which we are retweeting.

  # It will retweets the tweet having id tweet_id as authentication user.

  # It will returns the original tweet with retweet details.

  reply_text = "here is a replying message"

  Twitter.update( reply_text, "in_reply_to_status_id" => reply_status_id)

  # Use "in_reply_to_status_id" to reply  the existing status that the update is in reply to.

  # Here, the reply_text is  the reply message and, the reply_status_id is an ID of an existing status to which we are replying.

  # It will returns the replied new  Tweet.