لا

In a sentence

• لا أريد الذهاب إلى الحفلة.

  I don't want to attend the party.

  Here, 'لا' negates the verb 'أريد' indicating a negation of the desire to do an action.

• لَا، أنا لا أحب القهوة.

  No, I don't like coffee.

  Here, the first 'لا' is used as a simple negative response (no), and the second 'لا' negates the verb 'أحب' expressing a dislike.

• كل شيء واضح هنا، ألا تعتقد ذلك؟

  Everything is clear here, don't you think so?

  Here, 'لا' is part of the word 'ألا', which is used to form a negative question seeking affirmation.