有一读者问： 我在《英语学习》中遇到这样一句话：
(1)Jasper White is one of those rare people who believes in ancient myths.
许孟雄先生认为这个句子中的who believes应改为who believe。《新概念英语辅导材料》第二册（郭兴家、王福林编）的解释是： who believes in ancient myths是定语从句，修饰one，所以谓语用believes。《实用英语语法疑难解析》（李永生编著）的解释是： 定语从句的谓语动词的数，应由它所修饰的先行词的数来决定。如果根据意义确定该结构中的先行词是复数名词，从句中谓语动词则为复数形式，如：
(2)This is one of the most interesting questions that have been asked.
有时根据意义可判定先行词为one，特别是当one之前有the only, any等作定语时，那么定语从句中的谓语动词应采用单数形式，如：
(3)He is the only one of those boys who is willing to take on another assignment.
(4)Is there any one of you who wants to go with me?
另在《英语世界》某期第12页上有这么一句：
(5)Probably the story is one of those mysterious bits of folklore that reappear every few years, to be told anew in one form or another.
此句的that从句却又用复数谓语动词。种种说法，实不知孰对孰错，敬请指教。
按照语法规则而论，上述李永生等人的论述都是正确的。但语言实际与语法规则并不总是完全一致。从英语实际来看，与上述规则相反的情况确是为数不少，从句用单形动词、主句中用复形名词作先行词的现象可谓屡见不鲜。也可以说，这是英美人常犯的错误。但这似乎有点积重难返了。据有人统计，违反这条传统语法规则的人与遵照这条传统语法规则的人的比例约为2:1，有的人甚至说是5:1。有的语法家还为违反这条语法规则的现象找出了原因，即定语从句之所以用单形动词是受到了主句中one的影响的缘故。你所举的上述句（1）即是一例。这样的例证很多，再如：
(6)This is one of best books that has appeared this year.
(7)Really good talk is one of the great pleasures there is.
(8)This is one of the doors that was damaged.
(9)Washington is one of the few states that has such a reforestation requirement on its statute books.
(10)He effected one of the most difficult reforms that ever was accomplished by any statesman.
(11)One of the greatest and most serious strikes which has occurred in modern times will take place.
(12)She's one of those women who doesn't know a damed thing about furniture but believes she has a flair.
(13)Singing is one of the activities which generates the greatest enthusiasm and is a pleasant and stimulating approach to the culture of the foreign people.
最后似应指出，有人认为这种不合语法的情况多出现在美国英语和口语中。
