这些词组后加名词作主语,其后的谓语动词的单复数根据什么决定?
a quantity of, quantities of
a mass of, masses of
amount of, amounts of
a variety of, varieties of
你的问题请参考“英语语法网”的以下文章:
1. quantity
http://www.yygrammar.com/Article/201205/2946.html
2. amount
http://www.yygrammar.com/Article/201503/3825.html
http://www.yygrammar.com/Article/201301/3136.html
3. variety