Really good presentation on Punctuations, this will help you in constructing your sentences.

Dear Class,

                   This presentation is on Punctuations (when to use comma, full stop etc). This presentation is really fun with animations and sound effects. Do download it and study it carefully at home. You can also discuss it with me on your blog. 

http://jmp.sh/v/DtuIzmpLfzLtnC7Qv2bE