Case Name
and Typical Meaning / Use

Sing./Plural
Endings

Examples

Nominative

The "subject case": the subject is the word found by asking WHO or WHAT before the verb.

-ÊS

-ÊS

rês, rês

Rês mihi nuntiâta est.
  The matter was reported to me.
 
Multae rês ad hoc cônsilium Gallôs hortâbantur.
  Many things encouraged the Galls toward this strategy.
 

Genitive

The "possession case": The genitive word corresponds to the word that takes an apostrophe in English. If (A) is in the genitive, (A) possesses something else (B), with the emphasis falling on (B), so that (A) is somewhat like a modifier of (B): in student's book (= discipuli liber), the possession-word qualifies the meaning of the noun book. 

-EÎ,
-ÊÎ

-ÊRUM

reî, rêrum

Plus acquisisti dignitâtis quam amisistî reî familiâris.
 You have gained more in dignity than you have lost in property.
 
dê rêrum natûrâ
  about the nature of the universe

Dative

The "indirect object case": the indirect object is found by asking TO / FOR WHOM? or TO / FOR WHAT? after the verb. Certain verbs govern the dative.

-EÎ,
-ÊÎ

-ÊBUS

reî, rêbus

Huic reî idôneôs hominês dêligêbat.
  She selected people suitable for this matter.
 
Sed hîs rêbus tantum temporis tribuit, quantum erat properantî necesse.
  But he gave only so much time to these things as was necessary for one in haste.
 

Accusative

The "direct object case": the direct object is usually found by asking WHO or WHAT after an action-verb whose action has a receiver. "We hold these truths." The accusative is also used after certain prepositions.

-EM

-ÊS

rem,  rês

ûnam rem ad mê scrîpsistî...
  One thing you have written to me... 
 
Rês meliôrês quaerit.
  she is looking for better things.
 

Ablative

The "by-with-from case": Certain prepositions and certain verbs govern objects in this case. Used alone it can have an adverbial meaning, for example, to indicate by what means something is done.

-Ê

-ÊBUS

rê, rêbus

Nec eâ rê fruî volêbam quam furtô appetêbam.
  And I did not want to take enjoyment of that thing that I was seeking in the theft.
 
Hîs dê rêbus Caesar certior factus est.
  Caesar was informed about these things