kompleks

/kompleks/

Cases

SingularPluralWhen to use it
nominativekompleksthe complexkomplekslethe complexesthe plain dictionary form — the doer of the sentence
genitivekompleksnithe complex'skomplekslenithe complexes'the owner — whose it is
accusativekompleksnithe complex (as the object)komplekslenithe complexes (as the object)a specific, known object — whom or what
dativekompleksgeto the complexkomplekslegeto the complexesdirection or recipient — to where, to whom
locativekompleksdeat / in the complexkompleksledeat / in the complexeswhere it is; also having — mende bar, "I have it"
ablativekompleksdenfrom the complexkompleksledenfrom the complexeswhere 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
mykompleksimmy complexkomplekslerimmy complexes
yourkompleksingyour complexkompleksleringyour complexes
his / herkompleksihis / her complexkomplekslerihis / her complexes
ourkompleksibizour complexkompleksleribizour complexes
you all'skompleksigizyou all's complexkomplekslerigizyou all's complexes
theirkompleksleritheir complexkompleksleritheir complexes

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