uçebnik

/utʃebnik/

Cases

SingularPluralWhen to use it
nominativeuçebnikthe textbookuçebniklethe textbooksthe plain dictionary form — the doer of the sentence
genitiveuçebniknithe textbook'suçebniklenithe textbooks'the owner — whose it is
accusativeuçebniknithe textbook (as the object)uçebniklenithe textbooks (as the object)a specific, known object — whom or what
dativeuçebnikgeto the textbookuçebniklegeto the textbooksdirection or recipient — to where, to whom
locativeuçebnikdeat / in the textbookuçebnikledeat / in the textbookswhere it is; also having — mende bar, "I have it"
ablativeuçebnikdenfrom the textbookuçebnikledenfrom the textbookswhere 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
myuçebnigimmy textbookuçebniklerimmy textbooks
youruçebnigingyour textbookuçebnikleringyour textbooks
his / heruçebnigihis / her textbookuçebniklerihis / her textbooks
ouruçebnigibizour textbookuçebnikleribizour textbooks
you all'suçebnigigizyou all's textbookuçebniklerigizyou all's textbooks
theiruçebnikleritheir textbookuçebnikleritheir textbooks

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