"Seen" is the past tense form of the verb "see."
The past tense form is used to describe an action that was completed in the past. For example:
"I saw a movie yesterday."
"She saw the sunrise this morning."
"See" is an irregular verb, which means its past tense form is not created by simply adding -ed to the base form of the verb. The past tense form of "see" is "saw."
Here are some more examples of "see" in the past tense form "saw":
"I saw my old friend at the coffee shop."
"He saw the accident happen."
In conclusion, the past tense form of "see" is "saw."