疑问附加语 isn't it
"John is smart, isn't it?"
这个疑问句里的附加语（question tag）对吗？如果是不对的话，错在哪里？
在公共场所或办公室里，只要稍为留心，不难听到“ isn't it ? ”这个附加语。这种疑问句是英文几种疑问句中的一种，主要的用途在强制答话人提供问话人心目中的答案。
这个疑问句有一定的格式，即：
肯定叙述句（affirmative statement）＋否定附加语（见例 ①及②）
否定叙述句（negative statement）＋肯定附加语（见例③及 ④）
①Mary is happy, isn't she?
②They will come, won't they?
③Mary isn't sad, is she?
④They won't come, will they?
此外，附加语中的代名词（pronoun）和助动词（auxiliary verb）必须和叙述句中的相符。
这类疑问句看似简单，其实容易出差错。其中一个错误便是附加语的时态（tense）不对，如：
⑤You could hardly expect him to help you, can you?
⑥The minister will talk about regional cooperation, wouldn't he ?
另外一种错误是助动词的错用，如：
⑦The clerks are working hard, don't they?
⑧Betty won't be a sportswoman, can she?
“isn't it”的滥用
最常见的错误来自“isn't it”的滥用，如：
⑨Jason likes this book very much , isn't it?
⑩She can sing well, isn't it?
11.Our team won, isn't it?
12.Young Singaporeans have become achievement - oriented , isn't it?
13.All our teachers are dedicated, isn't it?
14.They will go shopping on Sunday, isn't it?
这6个错误的附加语改正如下：
⑨Jason likes this book very much, doesn't he?
⑩She can sing well, can't she?
11.Our team won, didn't it?
12.Young Singaporeans have become achievement - oriented, haven't they?
13.All our teachers are dedicated, aren't they?
14.They will go shopping on Sunday, won't they?
" lsn't it ? "在下列3个句子中才是正确的用法：
15.It is fine today, isn't it?
16.That story book is interesting, isn't it?
17.It is worthwhile learning a second language well, isn't it?
现在再看看“John is smart , isn't it ?”错在哪里。很明显的，错在附加语里的代名词：应该是“he ”，不是“it”，全句如下：
John is smart, isn't he?
