1 . It’s our duty to leave a better, cleaner and healthier planet for our children, so effective _________ (措施) are badly needed to maintain the ecological balance. (根据汉语提示单词拼写)

2 . In short, the tourism industry is facing t__________ (艰难的) challenges and it has to turn those challenges into opportunities. (根据中英文提示单词拼写)

3 . Keeping a diary can help us both express positive feelings and bring out n________ ones. (根据首字母提示拼写单词)

4 . China is a country under the rule of law and the legal aid system has been _________ (可使用的) to more people.