Make 5 questions (general, who-questions, 2 special, tag -question)
1.he was going to catch the 6 o'clock
2.he caught the 6 o clock train

He was going to catch the 6 o'clock train.
1.Was he going to catch the 6 o'clock train?
2.Who was going to catch the 6 o'clock train?
3.What was he going to do at 6 o'clock?
4. When was he catch the train?
5.He was going to catch the 6 o'clock train, wasn't he?

He caught the 6 o'clock train.
1. Did he catch the 6 o'clock train?
2.Who caught the 6 o'clock train?
3. Where did he catch 6 o'clock train?
4.Why did he catch the 6 o'clock train?
5. He caught the 6 o'clock train, didn't he?