用括号中所给词的适当形式填空。 1. ______ (teenage) want to go to the Watertown. 2. He got two ______ (Australia) stamps from his friend. 3. The Yellow River is the ______ (two) longest river in China. 4. Alice asks me ______ (polite) to put the things away. 5. The weather in Beijing is quite ______ (difference) from that in Guangzhou.