修饰单数可数名词：many a/an
修饰复数可数名词：(1)many(2)a good many(3)quite a few(4)a number of(5)scores of(6)dozens of(7)a few(8)several
修饰不可数名词：(1)much(2)a great deal of(3)a amount of(4)a little(5)a large sum of(6)sums of
修饰可数名词复数或不可数名词：(1)a lot of(2)lots of(3)plenty of(4)a quantity of(5)quantities of(6)some