teachers which one is correct in the following phrases?

  1. a piece of apple

  2. a piece of apples

  3. a part of an apple

  4. a part of apple

Besides, I saw apple is defined as N-VAR in Collins Dictionary. And one sentence given is:

His ongoing search for the finest varieties of apple.

Can I use apples here?

Thanks a lot!

closed as off-topic by Scott, jimm101, user66974, Chenmunka, Mitch Oct 17 '16 at 14:15

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  • 2
    Yes, it can be uncountable. I prefer apple and blackberry in my fruit pies. – WS2 Oct 14 '16 at 8:40
  • 2
    Yes. This fruit spread tastes mostly of apple. – Dan Oct 14 '16 at 9:12
  • 2
    In addition, 1 is correct, 2 isn't. 3 is also correct (4 isn't), but has a different meaning. The stalk or pips could be "part of an apple", but if you were offering someone something to eat, you would offer them a "piece of apple". – JonLarby Oct 14 '16 at 10:02
  • 1
    It's uncountable when speaking of apple flesh, or cooked apple, as a substance. 'Varieties of apple' means varieties of that particular species of tree, so the singular is correct. – Kate Bunting Oct 14 '16 at 14:08
  • Related: english.stackexchange.com/a/122321/191178 – Laurel Oct 14 '16 at 14:30