Sorry 4 bad english 
Your English is very good, do not worry.If you sell the Bitcoin after one year u dont have to pay income tax´es for Bitcoins.But its necessary to say, that holding one year means holding one year..
So if u buy 1 BTC on 1. June 2015 and 1 BTC on 1. July 2015.. u must hold the first BTC until 01. June 2016..
If u sold 1 coin between the both dates.. You alwas sell the first u buy (First In First Out)..
For trades with Bitcoins under a year u got a exemption limit of 600 €, after passing the limit u must pay income taxes.
Holding Bitcoins is not a problem, a have a lot BTC kept for more than year. However, I have few more questions and I will be grateful for answer.So if u buy 1 BTC on 1. June 2015 and 1 BTC on 1. July 2015.. u must hold the first BTC until 01. June 2016..
If u sold 1 coin between the both dates.. You alwas sell the first u buy (First In First Out)..
For trades with Bitcoins under a year u got a exemption limit of 600 €, after passing the limit u must pay income taxes.
1. What if I have Bitcoin address with a three incoming transaction: 20 BTC on 1. June 2014, 15 BTC on 1. September 2014 and 10 BTC on 1. December 2014? May I sell 20 BTC after 1. June 2015, 15 BTC after 1. September 2015 and 10 BTC after 1. Dcember 2015? I mean which account method is accurate: last in first our (LIFO) or first in first our (FIFO)? Explanation: https://en.wikipedia.org/wiki/FIFO_and_LIFO_accounting
2. May I fill tax declaration to declare income form selling Bitcoins only still pay null tax? Is it enough if I put list of my Bitcoins address and amounts of sold Bitcoins, to proof tax authorities that my income is free of tax?
