Verdana-formatted bold

 VERDANA-formatted bold italic
This is an example of Verdana-formatted "plain text" in a paragraph...interspersed with a little italic font.
It starts out as a Word-created RTF, imported into Mobipocket Creator to make a PRC file (which displays the Verdana font in the PC viewer, as expected).  Then I save the Creator HTML and any pictures into a zip and import those to Calibre.
When I imbed the "Verdana" font in Calibre to make my LRF, only the italic and bold words display in Verdana.  Everything else is in a serif font, probably the default Times New Roman.
I looked at the HTML paragraphs, and they all specify Verdana.  I'll admit I don't know how to read all the "Style" codes listed at the top of the HTML doc.
Any idea why my san-serif font insists on being displayed as serif?