What are the most frequent punctuation errors in English?

Application I have to draw design for an application in social web. And I can't to make myself do it :( I'm so lazy.

A gift for my mother's birthday. Today I have to buy a gift for my mother. It's quite difficult to choose something interesting. My city is full of shops, but they all sell identic garbage at most. Once I had gone through the shops for four hours to buy T-shirt and find nothing. Usualy sellers fill the hagers by the same stuff to create an impression of a big choise. Is it only in our shops?

First notebook entry: Introducing myself My name is Kirill, I'm 22 years old. I'm a chemist. I'm interested in science, phylosophy, psychology, cinema, music and many other things. I want to improve my English. I would be glad to help you with Russian and Ukrainian.