问题
填空题
根据句子意思和所给的首字母写出所缺单词。
1. Oxygen (氧气) is a kind of u_______ gas.
2. The Yellow River is the s________ longest river in China.
3. I think it u________ to see the ghosts (鬼). You must be joking.
4. There are many a_______ who want to fly to the moon.
5. I felt surprised and scared when I saw the t________ monsters.
答案
1. useful 2. second 3. unbelievable 4. astronauts 5. terrible
