Subject refers to the thing or person that is being talked about or described.
When a specified feeling or action is directed towards a thing or person is referred to an object.
Verb refers to the action words which helps in the formation of the main part of the predicate in a sentence.
In the above sentence,
The subject is graduates, as they are being talked about.
An object is poor writing skills, as this specifies a feeling
The verb is demonstrated, as it is the action word.