Ur, P. (2009). Grammar practice activities: A practical guide for teachers (Second edition.). Cambridge University Press.
Chicago-viite (17. p.)Ur, Penny. Grammar Practice Activities: A Practical Guide for Teachers. Second edition. Cambridge: Cambridge University Press, 2009.
MLA-viite (9. p.)Ur, Penny. Grammar Practice Activities: A Practical Guide for Teachers. Second edition. Cambridge University Press, 2009.
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