Определение to think back в Английский Язык Английский Язык словарь
If you think back, you make an effort to remember things that happened to you in the past. I thought back to the time in 1975 when my son was desperately ill Thinking back, I don't know how I had the courage. = look back
recapture the past; indulge in memories; "he remembered how he used to pick flowers"