Did you notice how subject is italicized in 5.9? In 5.12 you will see that direct object is italicized. The reason is that these are the technical terms used to describe a specific grammatical construction. The commentaries will use these terms, so you need to be learning them. You will come across words listed as nominative that will not be functioning as the subject of the verb. When this happens, tell yourself to have a little humility and realize that this is one of the grammatical constructions
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