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'?

Yes on all counts

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

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

1. Yes, all four sentences are grammatically correct.

2. In sentence #1, "He took a picture of the house," it can be understood that he took just one picture of the house. However, it is also possible for someone to take multiple pictures but still use the singular form "a picture" when speaking casually or informally.

3. In sentence #4, "He took pictures of the house," the plural form "pictures" suggests that he took more than one picture. However, it does not specify the exact number. It could be two, three, or even more. This sentence is more inclusive and does not limit the number of pictures taken.

4. If someone took just one picture of the house, it is grammatically correct to use "took a picture of" instead of "took pictures of." For example, "He took a picture of the house" would indicate that he took only one picture, while "He took pictures of the house" implies multiple pictures.

Remember that context is essential in understanding the exact meaning of a sentence. If the number of pictures is important to convey, it is best to be more specific by using quantifying words such as "one," "two," "several," or "many."