Ответ:

1. Mark didn't plan to travel....

2. It all started on Sunday morning.

3. He had been working...

4. His dad called him.

5. He wanted to see him...

6. He booked a ticket

7. by the time Mark arrived

8. the train had left.

9. he got on

10. He had been traveling for half an hour

11. when the train suddenly stopped.....