请仔细听下面一段文字，根据听到的内容补全空格中缺失的单词。I'm Wang Hong, a tour guide at Discovering China.I've been working as a tour guide for more than 10 years. My father was ____20_____, too.I learned a lot from him.I _____21_____ being a tour guide. I've _____22_____ to many places in China and abroad in the past 10 years. Every day is a challenge for me, working with different people, but it is _____23_____ and rewarding. I love working with people from different places. China has rich tourism resources and I am still _____24_____ to explore its wonderful natural scenery.