根据句意及汉语或首字母提示，用该单词的适当形式填空。 1. When we go to the desert, we'll see little v________ there. 2. May Day and National Day are both p________ holidays 3. I sat down to write my essay, but I found it was completely without i________. 4. Parents should e________ their children to behave well. 5. He is a busy teacher with little s________ time. 6. It was too late to s________ the dog. It died at last. 7. It's harmful for the villagers to eat or drink the p________ food or water. 8. We should protect the e________ and make our world more and more beautiful. 9. We are lucky to live in the new________ (社会), so we must study hard. 10. Look at this, it is a________ (模型) of a plane.