\documentclass[a4paper, 11pt,
  % twoside,
  formal title,
  title in boldface,
  % title in sffamily,
  % theorem in new line,
  % remove qed,
  colored solution,
  hide solution,          % Use this option to hide the solutions/answers
]{homework}


% EDIT THE FOLLOWING INFORMATION AS NEEDED

\pretitle{%
    \scshape
                    The University
    \hfill
                    The Program \& Level
    \\
                    Course ID \& Course Name
    \hfill
                    Year 2024--25
}

\title{%
                    Sheet 1. Title of the current file
}
\author{}
\date{%
                    % \TheDate{2024-01-01}
}


\begin{document}


Here starts the main text.


\section*{First theme}

We shall show that...

\begin{problem}
    A preliminary result.
\end{problem}

\begin{solution}
    \blindtext
\end{solution}

\begin{problem}[Brief description]
    One step ahead.

    \blindtext
\end{problem}

\begin{solution}
    \blindtext[2]
\end{solution}

At this stage, we may conclude that...


\section*{Second theme}

Now we look at...

\begin{problem}[Some prepration]

    This is the prepration for...

    \begin{enumerate}

        \item
            First question.

            \begin{solution}
                \blindtext
            \end{solution}

        \item
            Second question.

            \begin{solution}
                \blindtext
            \end{solution}

        \item
            Third question.
            \qedhere

            \begin{solution}
                \blindtext
            \end{solution}

    \end{enumerate}
\end{problem}

\begin{problem}[Another problem with many sub-questions]
    \leavevmode % so that the first item start in new line
    \begin{enumerate}

        \item
            First question.

            \blindtext

            \begin{solution}
                \blindtext[2]
            \end{solution}

        \item
            Second question.

        \begin{enumerate}
            \item
                First sub-question.

                \blindtext

                \begin{solution}
                    \blindtext[2]
                \end{solution}

            \item
                Second sub-question.

                \blindtext

                \begin{solution}
                    \blindtext[2]
                \end{solution}

        \end{enumerate}

        \item
            Third question.

            \blindtext[2]

            \begin{solution}
                \blindtext[2]
            \end{solution}

        \item
            Conclusion.
            \qedhere

            \begin{solution}
                \blindtext
            \end{solution}

    \end{enumerate}
\end{problem}


\end{document}