有一些读者来信问到一些有关关系代词的问题。这里，我们先讨论两个有关关系代词的问题。
第一个问题是： 关系代词who与指人的that有什么区别？
一般说来，先行词指人时，其后的关系代词多用who，不少语法学家认为这是现代英语一个趋向。但这并不意味着that已经过时。一位过世不久的英国语法学家曾说过： the man that built the house中that这种指代人的用法现在仍是正当的。所以我们不应对that指代人的用法有所忽视。至于who在现代英语中占有优势显然是由于它表人的意义较that明确的缘故。
具体地讲，下列情况一般多用who：
1. people和those（意谓“人们”）之后，如：
(1)People who live in the south of England speak in a different way from people who live in the north.
(2)Those who do not wish to go need not go.
2. 代词之后，如：
(3)He who does not work, neither shall he eat.
(4)All who heard the story were amazed.
(5)Any who refused would have to go, he declared.
(6)She is the one who grumbles.
3. 在非限制性定语从句中，如：
(7)I will pardon him, who is honest.
4. 在接续性定语从句中必须用who，如：
(8)I met Mr. Smith, who told me the news.
5. 在下面的分裂句中：
(9)It isn't only homicidal maniacs who are dangerous.
（意谓“不仅杀人狂是危险的”，如用that则会被理解为一未完成句，意谓“不仅危险的杀人狂”）
6. 在下面句子用作缩合连接代词时，如：
(10)Who steals my purse steals trash. （who=he who或anyone who）
(11)I've found who you were looking for. （who=the one who）
指人的关系代词that则多用于下列一些情况：
1. 先行词泛指一类人时，如：
(12)He is a man that is never at a loss.
2. 先行词兼指人与物时必须后接that，如：
(13)He was watching the children and parcels that filled the car.
(14)A victim is a person, animal or thing that suffers pain, death, harm, etc.
3. 先行词前有形容词最高级、序数词或only等词时（这种先行词亦属于类指，故较常用关系代词that），如：
(15)I knew her father for the simplest, hardest-working man that ever drew the breath of life.
(16)You are the only friend （that ）I have.
(17)He said she was the first woman （that ）he had ever looked at to love.
4. that常用作宾语，如：
(18)He was the man that the bottle fell on.
(19)The man that you saw this morning is my uncle.
5. that常用作表语，如：
(20)He's not the man （that ）he was.
(21)That is Mrs. Smith, Mary Brown that she was.
（用that指婚前情况，如用who则表已死）
(22)He died like the hero that he was.
(23)Dora did not reply, gentle creature that she was.
（that she was在此表原因）
(24)Fool that he was, he was not taken in this time.
（that he was在此表让步）
6. 在分裂句中，如：
(25)Was it you that called at my house yesterday?
7. 先行词前有指示代词same时，如：
(26)That's the same man that asked for help the day before yesterday.
8. 避免与who重复时，如：
(27)Who that you have ever seen can beat him in chess?
但下一句则多用who:
(28)Who's the man who has asked the question?
最后，应该指出，指代人的关系代词who与that用作宾语时可以省去（其实这种现象早已存在，并非省去），如上述例句（16）、（17）等。指代人的关系代词who与that作主语时亦可省去不用，如：
(29)You're the first man's ever been good to me. （man后省去主语that）
(30)I want a woman can milk. （woman后省去主语who或that）
that用作表语时有时亦可省去，如上述例句（20）。
第二个问题是： 关系代词which可不可以指人？
答案是肯定的。有的语法学家说，在古旧的和大众的英语中，关系代词which可以直接指代人。但在当代英语中，which指人时，多属不强调性别与个性的婴儿或儿童等，如：
(31)His mother had ten children, of which he was the oldest.
(32)He was the last child which was born.
偶尔也可指代不强调性别与个性的成年人，如：
(33)The 78 persons which will be screened in Havana by the Justice Department are all from the United States.
除此以外，which多用于指人的品质如身份、地位、人品等，如：
(34)He is exactly the man which his father wants him to be.
(35)Most of the critics have been kind. I only saw one which was not.
(36)He wanted to say goodbye to Christine, the only wife with which fate had seen fit to bless him.
由于which可表人的品质，所以在非正式英语中它可以代替用作表语的that,如：
(37)He fought you just like a gentleman which he wasn't.
which还可以用在代表人群的先行词之后，如：
(38)He saw his friend surrounded by a group which was laughing.
