词汇：babysit, camp, plan, hiking, Tibet, HongKong, away, postcard, send
短语：how long, get back, go hiking, babysit her sister, go camping, relax at home, on the 12th , go away, have a good time, show sb sth.
句型：
1. —What are you doing for vacation? —I’m visiting my grandmother.
2. —What’s she doing for vacation?—She’s going camping.
3.—When are you going? —I’m going on Monday.
4. —When is he going? —He’s going on the 12th.
