I know that most books are in a 'justified' paragraphing format but when I do change my document to that setting, it looks good but some parts are not good at all - the last sentence of the paragraph has only, say, three words and it is spaced out too much.
if your ms is going to be submitted to agents or publishers, you must NOT justify the margins... only left-aligned text is acceptable... if you're styling your ms to self-publish [and print it yourself], you can still use left-aligned, if you can't get the final line in paragraphs to 'stay together'... if you're going to send the ms to a self-publishing firm, ask them how they need the ms sent to them and if you have a problem they'll help you...
Thanks for the advice. I am only doing it because I like to make my document in book format - it is one thing that makes me comfortable to write my books, haha.
Full justification in published content is typically limited to columnized content, such as newspaper or magazine articles. For full page content, left-aligned is considered to have a better appearance. Full justification messes with the spacing between characters, but is used in columnized layouts because a flat right edge looks neater when there is an adjacent column with a "clean" left edge.
you should really get used to writing in standard ms format, if you want to have a career as a writer... if you're just writing for your own pleasure and won't be submitting any of your work to agents or publishers, then of course it doesn't matter how you format it...
When it is complete, I will eventually make another document transferring it to standard manuscript format. I know it seems a bit of needless fuss.
If your software is screwing up the final line of a paragraph, you've configured something wrong. I use LibreOffice, and I believe there's an option in the paragraph format to specify justification for the final line independent of the rest of the paragraph; in this case you'd use full justification for the paragraph and left for the final line.