A three-day school trip of my son is coming up. He is now nine years old but he has never slept away from home without his parents. Today, he said he might feel lonely during the trip because I would not be with him. So I tried to cheer him up and said "We can be together till the first day's morning and after the last day's evening. That means it is only a day that we will not be able to see each other, right? So don't worry too much." When my son heard of it, he had a relieved look on his face.