Question

1. He took a picture of the house.
2. He took four pictures of the house.
3. He took some pictures of the house.
4. He took pictures of the house.
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Are they all grammatical?
Does #1 mean that he took just one picture?
Does #4 mean that he took more than two pictures? If we took just one picture, can't we use 'took a picture of'?

Answer 1

Yes on all counts

Answer 2

I agree, but #4 would indicate that he took more than <I>one</I> picture. It is plural but doesn't designate the number.

I hope this helps a little more. Thanks for asking.