Conjugate the verb can in past?

The verb "can" is a modal verb and doesn't have a simple past tense form. Here's how you express the past tense of "can":

* Could: This is the past tense of "can" and is used to express ability, possibility, or permission in the past.

Examples:

* I could swim when I was a kid. (Ability)

* We could see the Eiffel Tower from our hotel room. (Possibility)

* You could leave early if you wanted. (Permission)