1. It seems that someone is calling your name. 2. It seems that someone is knocking on the door. It may be your parents. Just go and have a look! 3. I just got back less than ten minutes ago. 4. I just got back form a trip/business trip in beijing. 5. He has gone to beijing for travelling/business yesterday. 6. How long do you need to spend on your trip/business trip in beijing? He is going to have a trip/business trip in beijing for six days.