If I have justified alignment and insert a line break (i.e. Shift + Enter),
why does it space the entire line from left to right margin??? I know I can
turn this off through Tools, Options but I am wondering why it does this in
the first place since Word won't do this on a the last line of a paragraph.

SweetPea

In Word's "normal" logic (that is, without modifying it through Tools |
Options | Compatibility), the last line of a justified paragraph is
never justified. If you go to the end of the paragraph and insert a
Shift+Enter line break, the line with the words on it *is no longer the
last line of the paragraph* -- the last line is the one containing the
paragraph mark. The line with the words on it is now the next-to-last
line, so Word justifies it. When you check the option, you're modifying
Word's justification logic to say "now consider the line with the words
to be the last line, even though it isn't really."

The key question is, why are you using a line break instead of a
paragraph mark in this situation?

--
Regards,
Jay Freedman
Microsoft Word MVP        Word MVP FAQ site: http://www.mvps.org/word