"Reptles: cold blooded animals that creep or crawl along the ground whose skin is covered by horny plates or fish-like scales (eg: snakes, lizards, crocodiles and turtules). The majority lay eggs, but some give birth to live young"

Two questions need resolving.

1) Why did the author use whose skin is here? Isn't skin a countable word? In Oxford, they said that: Skin 1)[U, C] the layer of tissue that covers the body:
to have dark / fair / olive, etc. skin Ç The snake sheds its skin once a year. Ç cosmetics for sensitive skins Ç skin cancer

I cannot understand when it becomes  an uncountable noun and when is not.

2) What do they mean by live young in the last line?

3) Is the term by nature equal to naturally?

ex: Mariam is bright by nature

Mariam is bright naturally?

Spectacled-Girl wrote:

Hi there, 1) The author wants to emphasis the skin of the reptiles thus he uses 'whose skin'. The 'whose' can also be used in another way; -Eg: Peter is an American boy, whose skin is fair. 2) The 'live young' in this sentence simply means 'the babies of the reptiles' 3) I am not sure but I think 'by nature' and 'naturally' has the SAME MEANING but they are being used differently. Looking at your two sentences, the first one is correct but the second one is not. You can also form your sentence in this way: -- By nature, Mariam is bright. NOTE: It is 'reptiles' not 'reptles' Hope that I have helped in some way, and pardon me if I am wrong.

Oh, thanks. But how to correct my second sentence using "naturally"?

I know the function of whose here, but wonder why he use is, not are, and when to use skin as an uncount or count noun?

Spectacled-Girl wrote:

Belly wrote: Oh, thanks. But how to correct my second sentence using "naturally"? I know the function of whose here, but wonder why he use is, not are, and when to use skin as an uncount or count noun? naturally [adverb] 1) as might be expected; 'naturally, the lawyer sent us a huge bill' **2) according to nature; by natural means; without artifical help; 'naturally grown flowers' ''...whose skin is...'' Take note of the bolded word. It is given as skin, no 's', thus this means that there is only one skin which is a countable noun. Whenever there is a countable noun, we use is or was (depending on whether the context is present or past). And, whenever there is an uncountable noun, we use are or were because uncountable means 'cannot be counted' or we can put it simply as 'a lot' thus we cannot use 'is' or 'was' I will give you one example: --- There are hairs on the floor. [In this case, 'hairs' are an uncountable noun so we use 'are'] --- Look, there is a bird on the tree. [In here, 'bird' refer to one as there is no 's', thus this is a countable noun so we use 'is'] NOTE: It is 'countable' and 'uncountable'; not 'uncount' or 'count'.

Perhaps you didn't get my idea, so here it is:

They use "reptile:cold blooded animals that creep or crawl along the ground  whose skin is", well, animals is a plural noun so I wondered why we use is here.

In my dictionary (Oxford), it says the word can be used as (do we need as or in here?) both uncount noun (uncount noun is a real word, as Oxford says). Here is what exactly it says about the first meaning of skin:

Can you see [U,C] symbol? I don't know whether it indicates the word can be used in both way or it depends on the context meaning. If it depends on the context meaning, I wonder which meaning will fit each case. The definition here is too ambiguous, too vague indeed (Another question: Can we add indeed after too?)