TMG is designed to produce "real" narrative reports - not just birth/marriage/death in narrative followed by a bunch of bullet points, which has been traditionally the case for other programs that offer "narrative" output. A few others now have something like what TMG has had for decades, but still not as flexible.
TMG does this with "Sentence Structures," often called just "Sentences," which assemble the data in the date, place, memo, and name fields together with other text and punctuation in very flexible ways. There are standard Sentences for each Tag Type, and users can modify those, or design their own Tag Types and Sentences, or modify the Sentences in individual Tags. The result is you get real narrative output, complete sentences, for all events. If you use only the defaults it gets pretty repetitious, but if you want to invest the effort you get "handwritten" text. See, for example, this page on my website for Robert Cobb. The body of the narrative there is directly from TMG.
By using a couple of standard Tag Entry screens with only the standard elements instead of customizing the tag entry screen for each Tag Type, TMG lets users create unlimited numbers of Tag Types with great flexibility. The power is in the highly customizable Sentences.