It's an AutoCorrect option, "Capitalize first letter of sentences".
See
http://www.word.mvps.org/FAQs/Formatting/TameAutoFormat.htm.
But if you're getting this on every LINE instead of just every
paragraph, that means you're hitting Enter at the end of every line.
Don't do that! Just let Word automatically wrap the text to the next
line, and hit Enter only at the end of a paragraph.
--
Regards,
Jay Freedman
Microsoft Word MVP
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