How do I bold specific words in VBA macro for word?

The macro works like so.....I build a string, then apply the string to the
Sheet's range text property.  The problem is that there are specific words
inside the paragraphs that must be in bold.  Is there command that I can put
into the string that will automatically cause the words to be in bold? If not
what are some ways that I can search for the words and bold them?

Thanks,
ACFalcon