By a calendar I'm assuming you mean a table that you made in Word either youself or using one of the things from the project gallery (which will be based on a table). Illustrator really doesn't have the import filters for this and Word really doesn't have the export filters for it. Adobe Indesign can import Word and retain formatting.
If you have Powerpoint and don't care about editing the stuff later, you can import the Word file into a Powerpoint page and save as TIFF. Then place the tiff into Illustrator.
If you do anything fancy in Word, the likelihood of it coming out well in Illustrator is not great since Illustrator is a far more powerful graphics app, using different resolyions, color charts, etc.