Converse of object

• study: But I confess that I am now inclined to think that there is a finer way of studying ornithology than this.

Modifies a noun

• student: On the main street we bumped into an American ornithology student who was studying in the area.

Noun used with modifier

• field: However, we welcome papers from any part of the world that are of general interest to field ornithology.