I need to write two short paragraphs.

The first should be a description of the uses of a mobilie phone (I use my mobile phone to ......... It has got..... /functions )
The second should contain useful expressions needed when buying a mobile phone? Could you please help me?

2 answers

First, list for me what uses your phone has.

Then we can work on the second.
Present perfect: http://www.englishpage.com/verbpage/presentperfect.html

Past perfect: http://www.englishpage.com/verbpage/pastperfect.html

See other tenses listed on the left side of those webpages.