CAN-CAN'T / COULD-COULDN'T

Here you have different videos explaining the most important aspects in verb CAN .
Aquí tenéis diferentes videos explicando los aspectos más importantes del verbo can que ignifica poder, saber o poder hacer algo.

1. PRESENT

2. EXPRESSION

3. FORM: AFFIRMATIVE, NEGATIVE AND INTERROGATIVE

4. CONSTRUCTION: I  -  you... ?

5. PAST

6. FORM: AFFIRMATIVE, NEGATIVE AND INTERROGATIVE.