2.
Good morninig,guys!
I am on duty today.Thank you for giving me this opportunity to serve for our class and I will do my utmost not to let you down.
So,if you have any problems which not beyond my arrive,you can ask for me whenever I am free.And it's my honore!
I promise that I will keep our classroom clean and tidy all day.So is the blackboard,you will not see anything which have nothing to do with the proper subject.Of course,expect the notice of our headteacher and my name.For I am on duty today and I want leave a good impress in your mind.When you see my name on the blackboard,you will assosiate a happy and neat day today!
But,if I have accomplished the work very good,you can't call me do it day by day.I am a student rather than a dustman.Well,I just make a joke,I welcome you to ask me to service for our big family!
That's all.Thank you gor your time.