根据句意及首字母补全在本课中出现的单词。 1. Mr White gives us some good a ______. 2. Can you s______ your name, please? 3. Please give us a r______ quickly. 4. I don't know which book to c______. 5. D______ is a kind of valuable stone. 6. There is n______ in the classroom. 7. Easy is the o______ of difficult. 8. You need to eat a lot of v______.