\documentclass[a4paper,11pt]{letter}
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\author{Robert Kmieć}
\date{\today~r.}
\signature{Robert Kmieć}
\address{Robert Kmieć\\ Wałowa 5 Street\\ 56-400 Oleśnica}
\begin{document}
\begin{letter}{Tieto Ltd \\ Rysia 1a Street\\53-656 Wrocław,
Poland}

\opening{Dear Sir~or Madam,}

I~am writing in response to Your advertisement about internship.
I~would like to take participate in development of NFC stack in Linux
kernel.

I~have always wanted to be a~part of OpenSource community, and I~hope 
that Your company will help me, to become one.

My engineer's thesis subject was \textit{``A package for teaching real-time
systems using Linux Xenomai''}. During this project I~was working with
embedded systems and developing kernel modules for ARM based boards.
Now I~would like to expand my skills. I~am interested in new
technologies. Creating and developing them is my passion. That is why
I~would like to join Your team.

\closing{Yours faithfully,}

\encl{\begin{enumerate}
\item Curriculum Vitae
\end{enumerate}}
\end{letter}
\end{document}