a large amount of只能修饰不可数名词么

是的，a large amount of只能修饰不可数名词。

顺便总结一下l:

只能修饰可数名词的：a large/ great/ good number of,a good/ great many,dozens of,scores of,quite a few

只能修饰不可数名词的：a great deal of,a large amount of,quite a little,a large sum of

既可修饰可数也可修饰不可数名词的：plenty of,a lot of,lots of,a large quantity of,a good supply of

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