The negation frame
French negation has two parts: ne goes before the conjugated verb and pas goes after it. There is no equivalent of English do: I do not speak is simply je ne parle pas. The frame is the same for every person: je ne parle, tu ne parles, nous ne parlons.
How a negative sentence is built
pas stands directly after the verb, before any object or time expression.
Je ne parle pas français.
I do not speak French.
Elle ne travaille pas aujourd’hui.
She does not work today.
Tu ne comprends pas la question.
You do not understand the question.
The definite article stays (je n’aime pas le café), but un, une and des become de after pas: je n’ai pas de chat. More on this later.
Other negatives use the same frame with a different second part: ne fume plus (no longer smokes), ne comprends rien (understand nothing). The ne stays.
ne becomes n’ before a vowel
If the verb starts with a vowel or a silent h, ne becomes n’: ne aime → n’aime. This includes the common forms of avoir and être (n’ai, n’est). Before a consonant, ne stays: je ne suis pas. pas never changes.
Je n’aime pas le café.
I do not like coffee.
Il n’habite pas ici.
He does not live here.
Je n’ai pas le temps.
I do not have time.
Ce n’est pas possible.
That is not possible.
In spoken French
In conversation, native speakers often drop ne and negate with pas alone. You will hear this all the time, but for now write and speak with both parts.
Je sais pas.
I do not know.
Il est pas là.
He is not there.