昨天在批改学生作业的时候发现3B Unit 7 E 部分Listen and answer：Where is Bobby? (小狗在一只有扶手的椅子上）。有学生答 It's on the chair. 有学生答It's in the chair. 于是发了一个帖子：on the chair 还是in the chair. 特别说明了椅子是有扶手的。
之后我查了一下教师用书的参考答案两者皆可。
    后来我又上网查了一下，找到了下面的内容，与大家分享。

下面两本工具书却明确表示 armchair 只能和 sit in 搭配，不能和 sit on 搭配：

1. 周国珍主编《英语正误详解词典》（复旦大学出版社 2000年10月第一版 p61：

【误】He sat on his armchair, listening to music.

【正】He sat in his armchair, listening to music.

【译文】他坐在扶手椅上，听着音乐。

【解释】chair 是一般意义上的椅子，有靠背和座位可以视为平面，也可视为立体，因此介词既可用 on(平面)，也可用 in(立体)；而 armchair 指扶手椅，有靠背、扶手和座位组成，应视为立体，介词应用 in。又如：

The little boy sat unhappily in the big armchair. 小男孩不高兴地坐在大扶手椅上。

2. N. D. Turton and J. B. Heaton 主编的 Longman English-Chinese Dictionary of Common Errors(上海译文出版社1998年第11月第3次印刷) p27：

× She was sitting on a big armchair.

√ She was sitting in a big armchair. 她坐在一张很大的扶手椅里。

sit on a chair but sit in an armchair.

sit on后接 a chair；sit in则后接 an armchair。

那么，在英国英语和美国英语里，和动词 sit 及 seat 搭配的究竟是 in the / an armchair 还是 on the / an armchair 呢？请看以下真实例证：

1. 在BNC(英国国家语料库http://www.natcorp.ox.ac.uk)和BUY-BNC BRTISH NATIONAL CORPUS (UK,1980s-1993) (Mark Davies, Brigham Young University ) http://corpus.byu.edu/bnc/上共有5例包含on the/ an armchair的例证，其中无有1例 on the / an armchair和动词sit及 seat搭配的例证：

(1) Tom put a bundle on the armchair.

(2) He stood Willie on the armchair, took the towel away and placed the nightshirt over his head, cutting more away from the hem until Willie’s toes and hands came into view.

(3) “You can dry Sammy with that ole towel,” said Tom, indicating one lying on the armchair.

(4) I often have to get up with Graham, carry him into the living room and nurse him into the living room and nurse him on the armchair.

(5) And William standing in the middle of the kitchen looking pained and vaguely apologetic, and a reference book on Deaths among Rural Clergy during the Black Death lying recently discarded on an armchair.

共有142例包含 in the / an armchair 的例证，其中有78例 in the / an armchair 和动词 sit 及 seat 搭配的例证。

2. 在TIME CORPUS OF AMERICAN ENGLISH (1923-2006) (Mark Davies, Brigham Young University ) (http://corpus.byu.edu/time)上共有1例 on the / an armchair 和动词 sit 及 seat 搭配的例证：

1963/12/03 On opening night, the confused guests sat down on the armchair that was part of Jim Dine’s painting called Four Rooms, and piled their champagne glasses into the porcelain sink (painted black) that is part of his lesser work, Black Bathroom No. 2.

共有51例包含in the / an armchair的例证，其中有17例 in the/ an armchair 和动词sit及 seat搭配的例证。

3. 在BUY CORPUS OF AMERICAN ENGLISH (1990-2009) (Mark Davies, Brigham Young University) http://www.americancorpus.org/ 上共有21例包含 on the/ an armchair 的例证，其中有7例 on the / an armchair 和动词 sit 及 seat 搭配的例证。

有184例包含in the / an armchair 的例证，其中有52例 in the / an armchair 和动词 sit 及 seat搭配的例证。

从以上例证可以看出：在英国英语里，和动词 sit 及 seat 搭配的通常只能是 in the/an armchair，而不能是 on the/an armchair。在美国英语里，和动词 sit 及 seat 搭配的 in the/an armchair 和 on the/an armchair 的比率是68:8。也就是说美国英语里，和动词sit及 seat搭配的习惯是in the/an armchair，而不习惯用on the/an armchair。

由此可以得出这样一个结论：“坐在扶手椅上”习惯用 sit 及 seat 和 in the / an armchair来表达，而不用 on the / an armchair 表达。作为初中学生教材的译林版《牛津初中英语》应该采用大家都接受的说法。     

最后，再请看只接受 sit 及 seat 和in the/an armchair搭配的例证：

1. Oxford Collocations Dictionary for Students of English, 2nd edition (Oxford University Press, 2009):

be seated in / sit in an / the armchair

2.《牛津高阶英汉双解词典》(第7版)(商务印书馆 2009年) p90：

to sit in an armchair 坐在扶手椅上

3. Cambridge Advanced Learner’s Dictionary (Third Edition 电子版)：

She sat in an armchair by the fire, reading a newspaper.

4. (日) 市川繁治郎主编《英语搭配大辞典》(外语教学与研究出版社2006年10月第1版)p101：

be seated in an armchair

当然，如果是除 sit 及 seat 之外的动词(短语)和 the / an armchair 搭配，其中的介词除了用 in 和 on 之外，还可以用 into。例如：

1. Oxford Collocations Dictionary for Students of English, 2nd edition (Oxford University Press, 2009)：

be slumped in/be sprawled in / collapse into / flop into / throw yourself into / curl up in / ease yourself into / settle into an / the armchair

He eased himself into the big armchair.

2. Collins Cobuild Advanced Dictionary of American English (2007电子版)：

She was sitting in an armchair with blankets wrapped around her.

3. (日) 市川繁治郎主编《英语搭配大辞典》(外语教学与研究出版社2006年10月第1版)p101：

She leaned back in her armchair and looked at me.

He sank down into the armchair.

She settled comfortably into the armchair.  

Thank  you  for  sharing

似乎应该是分不同种类的椅子吧

谢谢楼主，受教了。

似乎应该是分不同种类的椅子吧

似乎应该是分不同种类的椅子吧