Sam was waiting for the train at the station.
1. Who was waiting for the train at the train station?
2. What was Sam doing for the train at the train station?
3. Where was Sam waiting for the train?
My brother answered a telephone call yesterday.
1. Who answered a telephone call yesterday?
2. What did your brither do yesterday?
3. When did he answer a telephone call?
Sam learned to swim when he was seven years old.
1. Who learned Sam to swim when he was seven years old?
2. What did Sam do when he was seven years old?
3. How old was Sam when he learned to swim?