again
1.again and again和time and again是“屡次地”或“频繁地”，now and again是“有时”或“偶尔”，only now and again是“难得地”。
2.比较下面两句：
- These shoes cost me as much again as the last pair I bought.
（这双鞋子价钱比我最近买的那双贵一倍［就是加上百分之一百］。） - These shoes cost me half as much again as the last pair I bought.
（这双鞋子价钱比我最近买的那双贵一半［就是加上百分之五十］。）
