>>I receive translated pages from professional translator in MS Word and PDF files<<
You should ask for the translations to be delivered to you in plain text. That would make your life easier. You'll have to insert your own HTML for bold, links, itlaics, etc - but if your translator knows any HTML they can supply that for you. If they don't, then you can have them mark where the beginning/end of these should be so you know where to place your tags.
The reason Microsoft Word doesn't work is because Word uses characters that are specific to the program only - meaning trying to us those characters in any other program will result in "what the hell are you talking about?" errors from anything that *isn't* Word. A good metaphor for what's going on is Word is speaking a dead language - like Latin - to everything around it. Other people who speak Latin (i.e. Word-related programs) can understand it just fine - but try going anywhere else and doing conversational Latin. People who speak French, et al might catch a few things, but form the most part, you're gonna get "Huh?"
This is why you don't want to use Microsoft Word for *anything* that's gonna be put on the internet and read by a browser (and don't argue that you can make websites with Word - have you *looked* at that code? Look at the doctype - it's even Word-specific). You get all those "?" and weird symbols. Get plain text, and you'll be fine.