词形转换。用所给单词的适当形式填空。 1. Listening to CDs is my best friend Susan's favourite. She is very _______. (music) 2. Alan is very smart and can always answer questions _______. (correct) 3. If there is no petrol in the car, it will be _______. (use) 4. Peter is very helpful and friendly. He is one of the _______ boys in our class. (nice) 5. At the _______ of next month, we'll go on a trip to the Fragnant Hills. (begin) 6. _______, the other climbers helped Simon to come down. (luck) 7. Giant pandas live in China, and they are very quiet and _______. (peace) 8. Many people all over the world do not understand the _______ of wetlands for birds in the nature reserve. (important) 9. If a bear is in danger, it attacks. So it is very _______ now. (danger) 10. When we saw the Eiffel Tower from the coach, we became very _______. (exciting)