To see internal punctuation at work, go to your public library on the morning that one of the librarians is reading to a group of children. Hear for yourself the effect of these internal punctuation marks on what the librarian is reading to the children.
Sentences are systematically arranged together to make paragraphs. Visualize, if you will, a table. The entire table is a paragraph. It has unity, and is well balanced. Its legs are the sentences it contains. Every sentence must fit that table. If the sentences do not fit, the table is unstable, and will look strange. Just as a table does not look right if it has two legs that are straight, another that is round, and one that is ornately carved, a paragraph does not look right if the sentences within it are written in a different style, or a different verb tense.
Now it is time to clear the confusion you probably have about the sub-title of this article. We all do our best to edit our work. But; I have found in my own experience that merely reading my work to my self does not always catch all of my typos, punctuation errors, and syntax errors. To catch these errors I have to hear what I've written while following along visually on the typed page. I used to have my wife read my manuscripts to me. Since her death, however, I have no one to read to me. Still, I need to hear my words so that I can know they are right.
Initially, I recommended using Microsoft Reader to listen to the text that you have written. During this past year, MS Reader has been revised in a manner that does not lend itself to use as a proof reading tool. Since I still need to hear my stories in order to edit and correct instances where I have used a wrong word, but spelled it correctly, thereby missing it when doing a spell check, or to revise a clumsily written sentence, I have been forced to find another text to speech program.
I hate to buy software without being able to try it, therefore, I did a Google search for "freeware, text to speech programs." I found eighteen programs that can be downloaded free of charge. One site lists a rating for each program, the date it was added to the site, and the number of downloads since that date.
Of the programs I downloaded and tested, NaturalReader 7 seems well suited for use as a proof reading tool. I like this program because it highlights the sentence being read and uses a contrasting highlight for the word under the cursor. This allows me to read the text while listening to it, thereby giving me two ways to find things I need to change.
Although my personal choice, at this time, is NaturalReader 7, other writers may find one of the other programs better suited to their needs.
Nearly all of these programs are available as freeware, however, the freeware versions are often stripped down versions, and while adequate the voices used still sound artificial. For a nominal cost, one or more full versions are available with a variety of natural sounding male and female voices. Moreover, the full versions of many of these programs are also capable of reading in various non-English languages and do so with correct pronunciation and inflection. Many of these programs also allow one to save the text as a mp3, or a wave file. This allows a writer to copy the spoken text to a CD or DVD for use as an audio book.
One final thought: by downloading these programs as freeware, one can test them and delete ones that do not work to one's satisfaction. Then, if desired, a full featured version of the most satisfactory program can be bought with some assurance that it will meet ones needs.