Help! I'm studying Latin!: Telling apart Dative and Ablative plural

This is going to be the first of three or four entries about how to tell apart the Dative and Ablative plural. I remember struggling with this discrimination as a beginning student. We're going to get there with a detour through the neuter rule.

First some practical info. Here are the forms:

Decl. Dat. Abl.
1 -is -is
2 -is -is
3 -ibus -ibus
4 -ibus -ibus
5 -ebus -ebus

Even the most cursory glance should tell you that they are the same. In fact, some textbooks even consider them to be the same thing in the plural. Run off and check that old edition of Pharr's Aeneid you've got kicking around. (Yes, I'm joking, I don't expect that you actually own that.)

The reason you want to be able to know the difference is that Dative and Ablative have very different uses and translations.

Now, before I get into a detailed discussion, I want to point out the Neuter Rule which we have all come to know and love. Nominative and Accusative share forms for all neuter forms, yet we manage to work with that. Look at the example:

Flumen per oppidum fluit.

This is pretty easy. Flumen could be a subject or direct object, and for the time being we don't have any other signals to help us out. The "per" signals in a big way: there's an object of a preposition coming, and it will be in the Accusative case. Which of course we see in oppidum. Finally we come to fluit which is looking for a singular subject and no direct object. Flumen must be the subject. So we get "the river runs through the town."

Getting more advanced, but not much:

Puella oppidum videt.

Puella is clearly the subject (let's ignore the possibility of Ablative). Then comes oppidum. Now, it is clearly not a subject. If it were, there would be a conjunction putting it on equal footing with puella, but there isn't. It must be the direct object. Here comes the trick:

Animal flumen transit. or even Flumen animal transit.

Both sentences mean the same thing. In both cases animal has a form that allows it to be either the subject or direct object. Same for flumen. Transit wants a singular object, and both nouns can fill that role. So how can we tell if it is "the animal crosses the river" or "the river crosses the animal"? Grammatically, Latin doesn't make that discrimination for us, so that's a dead end. Context to the rescue. Only one possibility makes sense, so that's what we go for. The animal crosses the river.

Next time: http://magisterpetrus.blogspot.com/2010/01/telling-apart-dative-and-ablative_27.html">Signals for Dative plural.