exim4 remove all queues or pending emails

1. list all queues or pending emails or not sent emails

command: 

$ exim -bp

2. remove a specific queue
command:
$ exim -Mrm EmailID

3. remove all queues
command:
$ exim -bp | awk '/^ *[0-9]+[mhd]/{print "exim -Mrm " $3}' | bash
or
$ exim -bp | exiqgrep -i | xargs exim -Mrm