1. Thanks to science we have learned to tell the difference between ________ (幻想) and reality.
2. It is ________ (不正常的) for a man to walk in his sleep.
3. The swimming club is open to families in the neighborhood without ________ (限制).
4. Urban inhabitants have to live with the ________ (特有的)noises of cities.
5. Don’ t let one failure ________ (使气馁) you, and try again.
6. Few people realized the ________ (重要性) of the discovery.
