one表示一,单数ones是表示复数的。替代词one或ones必须带有一个限定或修饰词,它们和所替代的名词中心词所指不一定是同一对象,这是替代词one或ones在用法上的一个重要特征。因为city是单数,所以选A,one1、C 2、A 3、D 4、Cone用于单数,ones用于复数,前两题都是特指的那一个,所以用one第三题行星用的是复数,所以是ones,第四题有any,所以要用单数,为one1C,指代hamburger 2A, 指代dress 3D,指代stars4C,指代boy楼主请记住,指代单数用one,指代复数用ones是不是很简单呢?c a d c替代词one和ones的用法: 1.one只能替代单数名词,one的复数形式ones只能替代复数名词。例如: My child doesn”t like this book.Show her a more interesting one. 2.替代词one或ones必须带有一个限定或修饰词,它们和所替代的名词中心词所指不一定是同一对象,这是替代词one或 ones在用法上的一个重要特征。例如: I don”t like this book.I”d like a more interesting one. 3.当替代词one或ones带有后置修饰语时,它们前面总有定冠词。例如: Our new cassette is more expensive than the one we had before. 4.当替代词one或ones在形容词比较级、最高级以及某些限定词如this,that, which和序数词等之后,可以省略。例如: This book is much better than that(one). 5.替代词one或ones通常不用在物主代词和名词所有格之后。如不可说my one(s),your one(s),Peter”s one(s)等等。one或 ones也不能用在own之后。 但是,如果有了形容词,one(s)可以和物主代词及名词所有格连用。如: My cheap camera seems to be just as good as John”s expensive one. 6.one作替代词时,在of前面不能用 the one来表示所属关系和类似概念。如不可说: *He put down his gun and picked up the one of Henry. 该用一个所有格来表示 He picked up Henry”s. 7.当两个形容词表示对照的意思时,不能使用替代词 one。仅在其中一个形容词后加上名词即可。例如: Don”t praise the younger child in the presence of the elder. 8.替代词 one如果不带任何前置修饰语,即它的前面既没有限定词,又没有形容词时,便不是替代名词词组的中心词,而是替代整个名词词组。这时,one=a+单数名词。例如: A cake made of wheat costs less than one made of rice.(one =a cake) one的这种用法是泛指同类事物中的任何一个,相当一个不定冠词,因此它没有复数形式。要泛指复数事物,只能用some。例如: Here are a few apples.Would you like some(=some of them)?举例说明1,yesterday i bought a new bike . it is blue.(it指前文刚提到的名词单数)2.i have many friends . they are all young.(they前文刚提到的名词复数)3.a bridge made of stone is stronger than one made of wood(one是单数与前文不定冠词对应4. the bridge made of stone is stronger than that made of wood.(that=the one 表示特指与前文定冠词the对应)5.the people who are standing there are those(=the ones) from japan(the ones 与those复数特指,与定冠词the people对应)6 .bridges made of stone are stronger than ones made od wood(ones不定指的复数,与前文的bridges 对应)