a great many 加可数名词复数
many a 加可数名词单数,但相当于many加可数名词复数
a number of 加可数名词复数,意为：一些,若干
large number of ,应当为a large number of或 large numbers of 与a great many 意思相近,意为：许多
a large amount of 加不可数名词,意为：许多
large amounts of 很少使用此种用法
a large quantity of 都加不可数名词,意为：大量
large quantities of 同上
a lot of 加可数名词复数或不可数名词,意为：许多
lots of 加可数名词复数或不可数名词,意为：许多
plenty of 足够的,或大量的 加不可数名词或 加可数名词复数
plenty of ,a lot of ,lots of ,a quantity of ,quantities of,a supply of ,supplies of,a mass of,masses of可与可数名词和不可数名词连用
a number of ,a variety of ,varieties of,a good/great many 后接可数名词复数a good/great many of 后面的名词复数前要有the/these/those/one's
a great amount of,amounts of ,a great/good deal of 后接不可数名词 a sum of 修饰货币