关于”A is n times large again as B”和”A is n times large as B”这两个表达是否等价的问题，以及它们是否都意味着A是B的n倍大，这需要我们进行深入探讨。
事实上，这两个短语在语义上存在明显差异。通常情况下，”A is n times large as B”是我们常见的表达方式，用来描述A在尺寸或数量上比B大n倍。然而，当使用”A is n times large again as B”时，其含义则有所不同。这个表达实际上强调A比B大出了整整n倍，即A在原有基础上增加了n倍于B的量。
为了更清晰地理解这一区别，我们可以参考一些权威词典中的经典例句并进行详细分析：
The cost is about half as much again as it was two years ago.
这句话的意思是，当前的价格比两年前增长了大约一半。这里的”half as much again”表明价格在原有基础上增加了二分之一。
Spending on health is half as much again as it was in 1998.
该句描述了卫生保健开支在1998年基础上增加了约一半。同样地，”half as much again”强调了开支的显著增长。
以上两个例句均来自《牛津高阶英汉双解词典》，它们准确地展示了”A is n times large again as B”表达中蕴含的倍数增长关系。
A similar wine from France would cost you half as much again.
这句话出自《柯林斯高阶英汉双解学习词典》，其含义是法国生产的类似葡萄酒价格比当前高出约一半。这里的表达方式与前面例句类似，都体现了”A is n times large again as B”的倍数增长含义。
以下是一些更多例句，用以进一步说明这一表达方式的使用场景：
This shirt cost me as much again as the last one I bought.
这件衬衫的价格是我上次购买的那件的两倍。这里的”as much again”表明衬衫价格在原有基础上翻了一番。
These shoes cost me as much again as the last pair I bought.
这双鞋的价格是我上次购买的那双的两倍。与上例类似，这里的表达方式也体现了倍数增长关系。
My new house is half as large again as my old one.
我的新房面积比老房大了一半。这句话清晰地展示了”A is n times large again as B”表达中蕴含的尺寸增长关系。
为了更直观地理解这种表达方式，我们可以进行一些比较分析：
We have a third as many students in our class as we had last term.
我们班的学生数量是上学期数量的三分之一。这里的表达方式与”A is n times large as B”类似，描述了数量上的比例关系。
We have a third as many students again in our class as we had last term.
我们班的学生数量比上学期增加了三分之一。与前面例句相比，这里的”again”强调了数量的增长。
Houses cost a third as much again this year as they did five years ago.
今年的房价比五年前高了三分之一。这里的表达方式与前面例句类似，都体现了价格上的倍数增长关系。
可以转换为：
Houses cost a third more than they did five years ago.
今年的房价比五年前高了三分之一。这个转换后的表达方式更加简洁明了地传达了价格增长的关系。