text: why are people on the internet so f*cking stupid, and unable to use proper grammar? seriously are you all mentally degranged or something?  your apathy towards your image makes you all look like retards. i'd like to ask you something. why did you call yourself [swear word] stupid, mentally deranged and retarded? you made four mistakes in your three sentences!  1) you put a comma before "and" in the actual question. you only use a comma before a conjunction (and, but, or, nor) when it is a compound sentence. you question is not a compound sentence because you could not say "why are people on the internet so [swear word] stupid? unable to use proper grammar? it doesn't work. to use a comma before and, you must say "why are people so [swear word] stupid, and why are they unable to use proper grammar.  2) you made a second mistake in your details. you did not put a comma after "seriously." you need a comma there because it is a parenthetical expression. basically, you could say "are you all mentally degranged [mispelled as it was in question] or something makes no change to the meaning of the sentence.  3) finally, you misspelled "deranged" (yes, spelling is part of grammar!). you spelled it degranged, which is not a word in the english language. even if it were correct in a foreign language, it would still be improper grammar because you cannot mix two languages in one sentence unless it is for demonstrative purposes.  4) you were redundant with the use of mentally and deranged. there is only one way to be deranged, and that is mentally. you should have just said "deranged"!  in response to your question, people are apparently unable to use grammar because they do exactly the same thing you do. they don't memorize their grammar rules, don't spell check, and don't care! they are too lazy! you can't criticise, because you do it yourself.  note: i have read this three (3) times, and it looks like good grammar to me. even if i made a mistake, at least i tried to proof-read it!  note: if a sentence/word in quotes is misspelled/has bad grammar, it is because i was mimicking the way you spelled it in your question. i removed swear words and replaced them with [swear word].  note: three-quarters of the people who answered your question have bad grammar! it illustrates my point perfectly!