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I had a friend recently ask me about the use of the particle "the" in different contexts that she was having trouble understanding and I found I was unable to explain the use. The lesson she had done was similar to this one:
Where "the" is explained as a word for a specific noun known to both speaker and the listener such as
The bike was red.
However a number of the examples she was given(and were not really explained in the material she showed me) were of the form
The bike is one of the most efficient means of transportation.
The squirrel is a small mammal
Neither of these examples are referring to a specific noun, they are referring to a generalization, "The bike" is true for every bike and the same for the squirrel example. Further to her confusion was that the sentences were not plural when referring to a generalization of "every bike" when she tried to correct the sentences as "the bikes are".
Would it be possible for someone to give me a explanation of this use or point me to something that has an explanation. I found it quite difficult to try and explain and the best I could come up with was that it's similar to "The idea of a bike is. . ." or "The idea of a squirrel is. . ." which I don't think is entirely accurate. The main trouble comes from "The" being used for a specific item, and in these cases the noun in question being used as a generalization. Am I just thinking about this wrong?