根据句意用所给单词的适当形式完成句子。 1. I’m sure that more and more people will cel ebrate their ________ (hundred) birthday. 2. There have been great ________ (improve) in both health care and personal safety. 3. Compared with the past, people are living ________ (healthy), longer lives. 4. She is very ________ (worry) about her sick father these days. 5.—What are you ________( plan)? —I’m thinking about giving a surprise to my mother for her birthday.