By the time I went to school ,I had prepared the lesson
It's not worth going shopping now. By the time we get to the shops, they will be closed.
I'm flying to the United States this evening. So by the time you receive this letter, I'll be in New York.
By the time Tony went to Mary’ home, she had gone to super market.
She had got on flight to American by the time he gone to the airport.
