The guard blew his whistle; she said something, but it was lost in the clanging of the bell and the hissing of the engine. I had to run back to my compartment. I watched her as the platform slipped away. She was alone on the platform and did not move, but she was looking at me and smiling. I watched her until the signal-box came in the way, and then the jungle hid the station. I could still see her standing there alone.
1. What was the girl doing when the train left the platform?
2. Why could the author not hear what the girl said?
3. How long did the author keep watching the girl?