How to use the Parallel package with proper environment options?

Question

If I use:

\begin{Parallel}[c]{0.47\textwidth}{0.47\textwidth}
\ParallelLText{paragraph 1 left}
\ParallelRText{paragraph 1 right}
\ParallelPar
\ParallelLText{paragraph 2 left}
\ParallelRText{paragraph 2 right}
\ParallelPar
\end{Parallel}

I get:

paragraph 1 left          paragraph 1 right
paragraph 2 left          paragraph 2 right
                    1

If I use:

\begin{Parallel}[p]{\textwidth}{\textwidth}
\ParallelLText{paragraph 1 left}
\ParallelRText{paragraph 1 right}
\ParallelPar
\ParallelLText{paragraph 2 left}
\ParallelRText{paragraph 2 right}
\ParallelPar
\end{Parallel}

I get:

                    1

paragraph 1 left
                    2

paragraph 1 right
                    3

paragraph 2 left
                    4

paragraph 2 right
                    5

What should I use in order to get:

                    1

paragraph 1 left
paragraph 2 left
                    2

paragraph 1 right
paragraph 2 right
                    3

? Can this be achieved with parallel? If not, what are the options?

Please let me specify that I'm starting to work on a book (+300 pages) that will have to be entirely in the desired form (even pages in one language and odd pages in another language; all paragraphs will have to be synchronized, e.g. paragraph#1_right will be the translation of paragraph#1_left).