Present Perfect

1. Question

1.1. Where have you been?

1.2. Has she played basketball?

1.3. How long have they lived in France?

2. Negative

2.1. He hasn't done his homework.

2.2. You haven't answered my question.

2.3. It hasn't known us.

3. Affirmative

3.1. He has known who they are.

3.2. They have promised to buy me a Husky dog.

3.3. We have been to California.

4. Use

4.1. An action or situation that started in the past and continues in the present.

4.2. An action performed during a period that has not yet finished.

4.3. A repeated action in an unspecified period between the past and now.