“Nicht” and “kein” are both forms of negation. “Nicht” means not and “kein” means no, not a or not any.
“Kein” is used to negate nouns that have no article or are preceded by an indefinite article. “Kein” precedes the noun in the sentence. It is declined in the same way an indefinite article would be declined in that sentence. Therefore make sure you know the declinations of the indefinite articles in each case!
Das ist kein Hund.~That is not a dog.
Es gibt keine Süßigkeiten mehr im Haus.~There are no sweets left in the house.
“Nicht” negates nouns preceded by definite articles and possessive adjectives. “Nicht” mostly follows the verb, and usually precedes the part of the sentence you want to be negated. If you want to negate an entire sentence then “nicht” will come last.
Das ist nicht mein Bruder.~That is not my brother.
Gestern war es nicht kalt.~Yesterday it wasn’t cold.
However, there are exceptions. With modal verbs and the future tense the “nicht” is placed before the infinitive or infinitive phrase.
In the perfect tense “nicht” precedes the past participle.
Wir haben uns nicht ausgeruht.~We didn’t relax.
“Nicht” comes before all of the following: adjectives, prepositions and adverbs.
Sie ist nicht glücklich.~She is not happy. (adjective)
Ich komme nicht aus Deutschland.~I don’t come from Germany. (preposition)
Wir trinken nicht jeden Tag Kaffee.~We don’t drink coffee every day. (adverb)
Let’s look at reflexive verbs. The negation “nicht” follows the reflexive pronoun after the verb.
Wir verstehen uns nicht gut.~We do not get on well.
With separable verbs the “nicht” follows the verb like normal verbs. It is then followed by the prefix.
Er steht nicht auf.~He is not getting up.
If there is a direct object (accusative) in the sentence, “nicht” will come after the direct object.
Ich esse den Pfirsich nicht.~I am not eating the peach.
Sometimes you can change the position of “nicht” to place emphasis on a point.
Ich gehe am Samstag nicht zum Haus meines Freundes.~I am not going to my friend’s house on Saturday. (not to my friend’s house is emphasized)
Ich gehe nicht am Samstag zum Haus meines Freundes.~I am not going to my friend’s house on Saturday. (not on Saturday is emphasized)
Let’s take a look at a few other negative words and phrases. They follow the same rules as those stated above.
Du isst nie Eier.~You never eat eggs.
Leitrim hat die All Ireland im Fußball noch nicht gewonnen.~Leitrim have not won the All Ireland in football yet.
Ich sehe kaum fern.~I hardly watch tv.
Ich verstehe nichts.~I understand nothing.
Nichts Neues.~Nothing new.
Er will mit niemandem sprechen.~He doesn’t want to talk to anybody.
Wir können das Auto nirgendwo sehen.~We can’t see the car anywhere.
HI -- thanks for the article....i was wondering about the following sentence: Es wäre besser, wenn der junge Mann nicht 20 Zigaretten pro Tag rauchen würde. I was sort of expecting: Es wäre besser, wenn der junge Mann keine 20 Zigaretten am Tag rauchen würde. I am a bit confused now about nicht vs kein.....thanks for any clarification.