1. When we go home, we should (应当) turn off the lights in our classroom.
2. John is a doctor. He works in a hospital.
3. It’s seven in the evening. Helen is doing her homework ,but her parents are watching CCTV news .
4. It’s very cold outside . You can put on your coat .
5. Look at the clock on the wall. You can keep the time .
6. There are seven days in a week.