My classmate Paulina lives  and work in New York. He has been here for one year. She plans to stay in New York a long time. She worries every day about problems in New York, such as the high cost of living. Last year


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correction:

 My classmate Paulina lives  and work in New York.


-My classmate Paulina lives and works in New York.

He has been here for one year. (correct if you change "He" to "She")



She plans to stay in New York a long time. (correct)

She worries every day about problems in New York, such as the high cost of living. (correct)


Well done beginning!