What is the difference between effect and affect or inquire and enquire? I really don't know. My history teacher tried to explain the first one to me, but I don't think she succeeded much.

Is it just that effect is the noun and affect is the verb? But hey, what about the other one, and enquiry and inquiry and all that? What is the difference?
Sorry, but not quite true.

'Affect' is not a noun and should never be used as one, while the verb 'Effect' has a different meaning to the verb 'affect'. Ergo, the two words may not be used interchangeably.

"Affect" is a verb which means roughly 'to act upon in some way so as to bring about a discernible effect'. "She was affected by his grief...", "the music affects me deeply...", "this provision will not affect your rights...". You should never use 'effect' in these cases.

"Effect" is both a verb and a noun. As a noun, it describes a discernible condition or result of having been acted upon (affected). "The effect of his grief was greater sympathy...", "the music has a rousing effect on me", "the effect of the new provision was to curtail rights".
As a verb, it means literally 'to bring about'. So: "His evident grief effected a change in her sympathies...", "the music effected a renewed passion in me...", "the provision effected a curtailment of civil rights".

They are related, but distinct meanings, and cannot be interchanged without affecting (!) the sense of the sentence.
Excuse me, properlady, but, just for the record, "affect" can be used as a noun in very particular circumstances. In psychology, "affect" (with the stress on the first syllable) means feeling or emotion. A person who laughs instead of crying at a funeral might be said to show "inapproprite affect." I think the rest of your explanation is excellent.
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I'm afraid "affect" can also be a noun - though it may not be used much -...

\***"\, n. [L. affectus.]
Affection; inclination; passion; feeling; disposition. [Obs.]

\***"\, n. (Psychotherapy)
The emotional complex associated with an idea or mental
state. In hysteria, the affect is sometimes entirely
dissociated, sometimes transferred to another than the
original idea.

This comes from Webster
Affect is more commonly used as a verb. Effect Is usually a noun, but they can be used interchangably.
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Hi colleagues .. I'm a new member.

Thanks .. I learn something here.

Emotion: smile


I mean by "colleagues" the peaple that share me in a class or in a forum or in a work.. am I right ?!

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I suggest this be one of the FAQs.

Another one would be: lie, lied/ lie lay / lay laid
Effect is used in positive affirmations and sentences ( example : Special effects )

Affect is used in sentences expressing negativity ( Example ;Side Affects )

I hope, I was able to add value.