Questions & Answers about Iecur in corpore est.
Iecur is nominative singular, because it is the subject of est.
The full dictionary form is iecur, iecoris n. It is a neuter noun. In this sentence, iecur is the thing being talked about, so it appears in the nominative.
Because in here means in / inside / within in the sense of location, and with that meaning it takes the ablative case.
So:
- corpus = nominative or accusative singular
- corpore = ablative singular
Since the sentence describes where something is, Latin uses in + ablative:
- in corpore = in the body
This is a very common Latin pattern:
- in + ablative = location: in, on, inside
- in + accusative = motion toward / into
So:
- in corpore est = it is in the body
- in corpus would suggest movement into the body