How can I select a seat online for the train to Shenyang on the 21st?

You can choose your seat in Shenyang online by following the steps below:

1. Open the China Railway Customer Service Center website or mobile APP (such as 12306).
   
2. Enter “Shenyang” as the destination on the homepage or search bar.
   
3. Select departure location, departure date and time.
   
4. In the search results, select the train you want to take.
   
5. Click the “Book” or “Select a Seat” button.
   
6. Select the seat type according to your needs (such as hard seat, soft seat, sleeper, etc.).
   
7. Enter passenger information, confirm order and complete payment.
   

Please note that seat selection may be affected by factors such as train type, seat availability, etc. It is recommended that you book in advance to ensure a suitable seat.