a (large) quantiy of +不可数名词作主语,谓语动词用单数；

(large) quantities of +不可数名词做主语,谓语动词用复数。

a large amount of 与large amounts of的区别

只不过都是amount是修饰不可数名词：

 a large amount of +不可数名词，谓语动词用单数；

large amounts of+ 不可数n 谓语动词用复数。

从 a huge amount of 和large amounts of说开去，兼谈a quantity of 和quantities of的用法（转摘）

外研版选修7 module3 里有a huge amount of词组。其用法为:a large（great,good）amount of ＋不可数名词，谓语动词一般用单数；但（huge，great，good）amounts of ＋不可数名词，作主语时，谓语动词要用复数。

A large amount of damage has beend one by the earth quake．

Large amounts of money were spent on the bridge．

关于 a quantity of 和quantities of的用法：“a large quantity of 译为“许多，大量”其谓语由短语中的“quantity”形式决定。它是单数，不管修饰的是什么样的词，一律用单数。如果是quantities,则谓语全用复数。只与quantity的形式有关。

专家观点：

1. 徐广联在《大学英语语法讲座与测试》（华东理工大学出版社）中表示， a quantity of 只能修饰不可数名词，谓语动词用单数。 A quantity of 间或也可以修饰可数名词，例如， A quantity of baskets were on sale.

2.  张怀信在《英语高考活用图解辞典》（延边大学出版社）中讲到， a large/small quantity of 大量的 / 少量的（可以修饰可数名词或不可数名词），例如， I need a large quantity of oil (apples). quantities of 大批的，大量的，例如， Large quantities of polluted water are flowing into the sea. 该书所附〈语法祥解篇 --- 主谓一致〉还明确指出“在以上（ a lot of, lots of, plenty of, a large quantity of + 名词）的词组后面的名词是中心词，谓语动词根据后面的名词的数而定”。

3 ．顾南华在《中高级英语考试指南》（华中工学院出版社）中说， a quantity of, quantities of 可跟可数名词与不可数名词 , 并举有三例： There is a large quantity of milk. Great quantities of fish are caught on the high sea. Large quantities of water are needed for cooling purposes. 在 452 页讲到“ a quantity of + 不可数名词”，谓语只用单数，“ quantities of + 可数与不可数名词”，谓语要用复数。

4 ．章振邦在《新编英语语法》（上海译文出版社） 212 页中讲到， a quantity of 既可用于复数可数名词，也可用于不可数名词。例如 , A large quantity of flowers were heaped on the martyr’s tomb. A large quantity of beer was consumed. Quantities of food were on the table.

5. 刘锐诚在《学生使用英语高考必备》（中国青年出版社）中认为， a quantity of + 名词 [C,U][+ 单或复数动词 ] ， quantities of + 名词 [C,U] [+ 复数动词 ] 。

6. 张鑫友在《英语语法难题新探（句法篇）》（中国地质大学出版社） 529 页中说，在 …a large quantity of… 等短语后既可接复数可数名词，亦可接不可数名词。在它们分别和其后的名词构成短语作主语时，其谓语动词通常跟 of 后名词的具体情况而采用单数或复数形式。    

综上所述，结论就是：

1 ． a quantity of 后既可接复数可数名词，亦可接不可数名词。在它们分别和其后的名词构成短语作主语时，其谓语动词通常看 of 后名词的具体情况而采用单数或复数形式。如果是接不可数名词，则谓语用单数形式，如果是接复数可数名词，则谓语通常要采用复数形式（※偶而接单数式谓语，属非规范用法，宜慎用。）

2 ． quantities of 后既可接复数可数名词，亦可接不可数名词 , 后面的谓语都用复数形式。  

举例证明：

1．   On January 18, a large quantity of coloured photopaper, dried seafood, canned abalone, audio equipment and antibiotics worth HH$16million were found in four 40-foot containers, bound for… ( In brief--- China Daily, HK Edition, ,   P2)

2．   Besides, a large quantity of mail bags were found. ( US nationals arrested for DVD piracy---China Daily, , P1)

3．   An undetermined quantity of weapons and ammunition were also seized, the spokesman said. (Raid in karbala and shots fired in Baghdad ---China Daily, 2003102, P1)

4．   …and a small quantity of dangerous drugs were seized. (Travel scheme causes concern in HK---China Daily, , P2)A

5．   A quantity of fake certificates and official stamps were also seized. (Police seize 59 in major gang smash, ) ※

6 . “ …and a large quantity of drugs is reading different segments of society.” Wang said. (Zzzicit drug dealers executed----China Daily, , P2)