Hi everyone i am new here!!!

thank you for replying my answer in advance, i think the are serverl questions but the most important is i can express myself freely , i just can say those simply world. If there are some difficult scentences ,idioms and phrases , i will feel double.
i am a student who study science ,my specialized is information and technolog .In a week i will give my classmate a english lesson about The Telecommunications Revolution, i would like you can give my some advice and
some usefull material, for i cannot just to finish my task but give my clasmates nothing .
And there are anothor question i have successful register but when i log in ,it is showing some error ,in another way i can not know how to user the site.

thanks !!!