Peterson, P. W. (2005). Changing perspectives: A review of English tense system ( Intermediate/High intermediate). Washington, D.C: United States Department of State.
Trích dẫn kiểu ChicagoPeterson, Patricia Wilcox. Changing Perspectives: A Review of English Tense System ( Intermediate/High Intermediate). Washington, D.C: United States Department of State, 2005.
Trích dẫn MLAPeterson, Patricia Wilcox. Changing Perspectives: A Review of English Tense System ( Intermediate/High Intermediate). Washington, D.C: United States Department of State, 2005.
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