1.The teacher asked the boy :"when đi you invent these things?"
=>The teacher asked the boy when did you invent these things?
2.The alien asked me:"How many hands do you have? "
=> The alien asked me how many hands I have?"
1.The teacher asked the boy :"when did you invent these things?"
=>The teacher asked the boy when he had invented those things.
2.The alien asked me:"How many hands do you have? "
=> The alien asked me how many hands I had.