Questions & Answers about Ŝi fleksos la genuon, krom se la artiko doloros.
Because la genuon is the direct object of fleksos. In Esperanto, the direct object takes the accusative ending -n.
- Ŝi fleksos la genuon = She will bend the knee.
- The thing being bent is the knee, so it gets -n.
The basic noun is genuo. With the accusative ending, it becomes genuon.
Because la artiko is the subject of doloros, not the object.
In la artiko doloros:
- la artiko = the joint
- doloros = will hurt / will ache
So the joint is the thing that hurts. Subjects do not take -n.
Compare:
- La artiko doloros. = The joint will hurt.
- Ŝi fleksos la artikon. = She will bend the joint.
In the second sentence, artikon would take -n because it is the object.