Range.GrammaticalErrors (Word)

Returns a ProofreadingErrors collection that represents the sentences that failed the grammar check on the specified document or range.

There can be more than one error per sentence. If there are no grammatical errors, the Count property for the ProofreadingErrors object returned by the GrammaticalErrors property returns 0 (zero). For information about returning a single member of a collection, see Returning an object from a collection.

Set myErrors = ActiveDocument.Paragraphs(3).Range.GrammaticalErrors 
For Each myerr In myErrors 
 MsgBox myerr.Text 
Next myerr