Why "she seen" shouldn't be seen: exploring common grammar pitfalls

What kind of error is it?

Grammatical error related to verb tense and aspect

Why do people make this mistake?

People often make this error because "seen" is the past participle of "see", and sometimes it is mistakenly used in place of the simple past tense without the auxiliary verb "have".

What is correct?

The correct form is "she saw" for the simple past tense, or "she has seen" for the present perfect tense.