I
verb
BAD : She's studying history in Oxford University.
GOOD : She's studying history at Oxford University.
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See in 5
II
noun
BAD : Next July I'm going to the USA to continue my study.
GOOD : Next July I'm going to the USA to continue my studies.
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To refer to the work that a student does at a college or university, use studies : 'After the war he resumed his studies at the University of Turin.'
Compare: 'They are conducting a study of sex education in local secondary schools.'