Help:Convert a text formatted with a word-processor?
If you paste into Mediawiki a text coming from Microsoft-Word, you will notice that italics, bold and other formats are not recognized. For small texts, the easiest way is to format manually in Mediawiki. For bigger texts, you may prepare the text in Word before copying it. You will find some indications at Biowikifarm. Tell us whether it works. Another solution is to ask Word to convert automatically one paragraph mark or one linebreak into a space. If you want to preserve true the paragraph breaks, you need first to add a rare character manually, and afterwards, to replace them automatically by two paragraph breaks.
There are also on the Internet converters from Word to html. This language is understood by Mediawiki, but it adds many codes.