根据句意和所给首字母提示完成单词
1. It's quite dark outside. It's p__________ nine o'clock in the evening.
2. There are altogether seven p__________ in this passage.
3. I can s __________ my lunch with you if you forget to bring yours.
4. The cake t__________ sour. It may have gone off.
5. He likes collecting telephone cards. He is a telephone card c__________.
曲线是指（）