根据句意及首字母提示填空。
1. It's a p____ trip to Beijing.
2. Her s____were so soft that nobody in the room heard her coming in yesterday.
3. When we reach Mount Tai, we'll see plenty of h____ stones there.
4. Beijing is in the n____ of China.
5. Most of the doors of the buildings have the sign "Pull" or "P____".