The phrasal verb TO WRITE STH OFF means to consider sb or sth to be lost, hopeless, unimportant, etc.:
You shouldn’t write off school. Education is very important.
I think the coach has written off his team as far as this season is concerned.
Don’t write me off as your friend. I’m really sorry for what I did.
She wrote him off as soon as she learned he was lying to her.
I’ll help you find the book. You mustn’t write it off just yet.
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