Questions & Answers about Canis aquam e catino bibit.
Canis is nominative singular here, so it is the subject of the sentence.
A few clues help you see that:
- The verb bibit is third person singular: he/she/it drinks
- So the sentence needs a singular subject
- Canis can serve as that subject: the dog
Even though canis can also be a genitive singular form in other contexts, here the sentence structure makes it clear that it is nominative and means dog as the one doing the drinking.
Because aquam is in the accusative singular.
In this sentence, aquam is the direct object of bibit. It answers the question:
- What does the dog drink?
- Water
In Latin, direct objects are often put in the accusative case, and for a first-declension noun like aqua, the accusative singular ending is -am:
- nominative: aqua
- accusative: aquam
So aquam means water as the thing being drunk.