plakat

/plakat/

Cases

SingularPluralWhen to use it
nominativeplakatthe posterplakatlathe postersthe plain dictionary form — the doer of the sentence
genitiveplakatnıthe poster'splakatlanıthe posters'the owner — whose it is
accusativeplakatnıthe poster (as the object)plakatlanıthe posters (as the object)a specific, known object — whom or what
dativeplakathato the posterplakatlağato the postersdirection or recipient — to where, to whom
locativeplakatdaat / in the posterplakatladaat / in the posterswhere it is; also having — mende bar, "I have it"
ablativeplakatdanfrom the posterplakatladanfrom the posterswhere it comes from; also "than" when comparing
When to use each case
nominative
the plain dictionary form — the doer of the sentence
genitive
the owner — whose it is
accusative
a specific, known object — whom or what
dative
direction or recipient — to where, to whom
locative
where it is; also having — mende bar, "I have it"
ablative
where it comes from; also "than" when comparing

The endings are the same ones the pronouns wear — that page explains when each case is used.

With an owner

One ownedSeveral owned
myplakatımmy posterplakatlarımmy posters
yourplakatıngyour posterplakatlarıngyour posters
his / herplakatıhis / her posterplakatlarıhis / her posters
ourplakatıbızour posterplakatlarıbızour posters
you all'splakatığızyou all's posterplakatlarığızyou all's posters
theirplakatlarıtheir posterplakatlarıtheir posters

The overlap in the last rows is real, not a mistake: plakatları can mean "his / her posters", "their poster", or "their posters" — context decides.