\documentclass[mode = stationery]{hduthesis}

\usepackage{lipsum}
\usepackage [ mono = false ] {libertine}

\hduset
  {
    title      = Recommendation Letter for SAN Chi Nan,
    author     = YIP Tsz Ching,
    mail       = email@server.domain,
    date       = \today,
    watermark  = true
  }

\begin{document}

\maketitle

Dear Prof. Wong,

\lipsum[1-2]

\vfill \raggedleft

Sincerely yours,\\[4ex]
\includegraphics[ height = 2em ]{hdutitle}\\[2ex]
Professor of Department of Physics\\
Hangzhou Dianzi University (Xiasha Campus)

\vspace{\baselineskip}

\clearpage

\notelines[25]

\end{document}