I have some questions about grammar........

[RSM1234]

I never eat pizza - This an absolute. I DO NOT eat pizza.

I have never eaten pizza - this means the speaker has not yet had it .. though may do.

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Bring a friend - Is the present tense.

Brought a friend - brought is past tense.

However BOTH phrases can be used for events taking place in the future ie :

Would it be ok to bring a friend to your party tonight ?

Would it be ok if I brought a friend to your party ?

In situations like the above - English people use both phrases ... and we (I'm English) always understand what you are asking.


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Will peel the skin off .. - Only used to describe an action in the present

Would peel ... - used in the present todescribe an ongoing action that happened in the past.

ie :

My child will always interrupt me when I am busy. (Present only.)

My child would always interrupt me. Present description of past event.

As stated though would is also used in connection with future events as in the example about the friend and the party.

[GiddyGad]

I have never eaten pizza - this means the speaker has not yet had it .. though may do.

'have never eaten' is the result in the present, the present state - the first verb of the Predicate will always show you the tense of the sentence. Whatever the outcome: you may refuse to taste it, or try it, or ask how to...
Perfect isn't an action - it's the state of an action. It's called Aspect.
There are two Definite Aspects in English: Perfect and Continuous (or Progressive) - the former being the result of an action, and the latter being the process of an action; both definite Aspects are opposed to Indefinite Aspect, when you just name an action, and don't define its state.

Would it be ok to bring a friend to your party tonight ?

'to bring' is Infinitive, the name of a purpose. It's a name and doesn't answer the question 'When?"... What time is RSM1234?...

[GiddyGad]

what does the correct way to say :

*Would you mind if I brought a friend with me
or
*Would you mind if I bring a friend with me

The first sentence is correct - it's in the Subjunctive Mood. It means that the Past Tense form doesn't denote the action in the Past but lessens the insistence. It's regular and may be used freely.
It should be remembered though that only the first verb of the predicate shows the Tense of a predicate. It is called the finite form. As opposed to Verbals - non-finite forms - which cannot start Predicates.

[GiddyGad]

another Question is when i put Would .... for example i saw a sentnce with "would" and i dont understand why they put there

- this is the sentence :
* He would peel the skin off my head

why they didnt write will instead of would

'Would' is the past form of 'will' . You don't give the context of the sentence and it's difficult to tell if the sentence refers to the past events or is in the Subjunctive Mood.

[GiddyGad]

...My child will always interrupt me when I am busy. (Present only.)...

...My child would always interrupt me. Present description of past event...

NB
'Will' may denote some special insistence as in 'I'm trying to explain but you will not listen to me,' or 'You will all have seen from the handouts which you have in front of you...'

'Would' may denote a regular/repeated action in the past.