英语中的中位限定词是什么意思?a book of my friehd's 中"a" 和"my friend's" 属于中

限定词根据其位置的不同,可分为三类：
前位限定词,包括：all,both,half,double,twice,two times,one-third,two-thirds,what,such (a)等.
中位限定词,包括：the, a (an), this,that,these,those,my,your；John’s,the old man’s；some,any,no,every,each,either,neither,enough,what (ever),which (ever),whose等.
后位限定词,包括：one,two,first,second,next,last,(an)other,many,much,(a) few,(a) little,fewer,less,more,most,several,plenty of,a lot of,a great number of,such等.
当多个限定词修饰一个名词时,其顺序为：
前位+中位+后位+名词,如：
all my friends,half the time,his many books,twice his courage等.
值得注意的是限定词不能用来修饰代词,如不可以说both they,most they,而应用both of them,most of them的形式.