In the following text, identify the temporal expressions, events, and temporal relations. For each temporal expression, identify the tokens involved and the type (i.e., Date, Time, Duration, or Set). For each event, identify the main word that expresses the event and the TimeML type (e.g., Occurrence, Reporting, Perception, etc.). For each temporal relation, identify the times or events related and the type of the relation (e.g., Before, After, Initiates, Factive, Modal, etc..).

John began working on the homework shortly after noon. His professor had released it the previous week, stressing that it had to be done by the 15th of January. However, his professor came by before the end of seminar, saying the deadline is extended.