Sorry for being persistent, but the usage of "waste" is still bugging me.
(I'm not sure whether I should start a new thread under 英語勉強フォーラム as this thread is about JLPT...)
In my personal view, either way works, but the way of thinking of it is different.
Like Glenn said I don't have as much of a problem with making the plural form (are wastes) as others seem to either unless it is considered uncountable and therefore grammatically a bulk item (stuff, money, space, time etc).
Strange he didn't take exception to the inclusion of "a" in "a waste of time" which clearly indicates it is a countable noun.
Or should we say, "JLPT (all inclusive, because he doesn't allow for different opinions of different levels) is waste of time." ??
So far I could find only two online dictionaries who gives info regarding countable/uncountable/singular/plural on the word "waste". (English-Japanese I've got do not mention about this particular expression = (a) waste of time.)
LONGMAN Dictionary of Contemporary English
1bad use [singular, uncountable] when something such as money or skills are not used in a way that is effective, useful, or sensible
waste of
- Being unemployed is such a waste of your talents.
- Many believe that state aid is a waste of taxpayers' money.
- What a waste of all that good work!
- excessive waste in state spending
2 go to waste if something goes to waste, it is not used:
- Don't let all this food go to waste.
3 be a waste of time/money/effort etc to be not worth the time, money etc that you use because there is little or no result:
- We should never have gone - it was a total waste of time.
It has a few more entries, in a sense of "unwanted materials" it is uncountable, and as "land" it should be used in plural i.e. wastes. There's "a wate of space" which does not have any indication of countable/uncountable, I assume it is a set phrase.
CAMBRIDGE Dictionaries Online
waste Meaning in the Cambridge English Dictionary
Cambridge Advanced Learner's Dictionary
waste (BAD USE)
noun [S or U]
1 an unnecessary or wrong use of money, substances, time, energy, abilities, etc:
- That meeting achieved absolutely nothing - it was a complete waste of time.
- She's been unemployed for two years and it's such a waste of her talents.
- My mother couldn't bear waste - she always made us eat everything on our plates.
2 waste ground/land an area of ground in or near a city which is not built on, cultivated or used in any way:
- His body had been dumped in an area of waste land just outside the city.
My understanding from these dictionaries is;
(1) the noun "waste" can be either countable/uncountable depending on the usage,
(2) when "waste" means "bad use", we can say "a waste of time" or "waste of time" but not "wastes of time".
If the above is true, it is very interesting because being used in singular with article "a" means it is countable, while it is also used as uncountable.
I wonder if "wastes of time" is also valid - I found may "wastes of time" (134,000 hits) when checking with google but being found on the net does not always mean it is grammatically correct, so I'm not really sure.
Or my understanding is wrong? Or even though "wastes of time" is not grammatically correct if strictly speaking, yet is very commonly used? (There are many such words/expression in Japanese, so I wonder if this could be the case.)
If my understanding is correct, then I have further questions.
1. Are there any other nouns similar to this, which are used in singular or as uncountable but not in plural?
2. When subject is plural, what is the correct usage - using "waste" as uncountable noun?
In Japanese basically we do not have singular/plural (at least not like English and many other European languages), and I often get confused and make mistakes about singular/plural, countable/uncountable, with or without article (a, an), which pronoun to be used, etc.
I really want to know what is correct and what is incorrect, and any help would be appreciated.

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