This is not a Word issue, and you'll do much better Googling for an answer.
My recollection is that Full Block has all paragraphs left flush. Modified
Block has the date centered below a letterhead (or the date and sender's
address aligned left at the center of the document) and the Complimentary
Close and Signature aligned left at the center of the document.
--
Suzanne S. Barnhill
Microsoft MVP (Word)
Words into Type
Fairhope, Alabama USA
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