tell me whats wrong with this sentence

'The teacher should have taken more time.'
teacher- subject
should- helping verb
have- helping verb
taken- action verb

I don't see anything wrong with this sentence. You've also identified the parts of it correctly.

ok, i guess my teacher marked it wrong by accident

The sentence "The teacher should have taken more time" appears to be grammatically correct. It follows a subject-verb-object structure, where "teacher" is the subject, "should have taken" acts as the verb phrase, and "more time" functions as the object.

However, if you're asking what the potential issue with the sentence could be, it may depend on the intended meaning. Without more context, it's difficult to say if the sentence is problematic. But in terms of grammar and syntax, the sentence seems correct.