Instrument
The data collection instrument consists of two parts. The first part is about the subjects’ personal information; the second part is the Teacher Textbook Evaluation Scale, which elicits the criteria of a textbook for English course. “Teacher Textbook Evaluation Scale” was adapted to Turkish by the researcher. The original version is “Teacher Textbook Evaluation Scale (TTES)”. This scale was developed by Sung Kyun Kwan University in 2000. The version, which was adapted into Turkish, consists of 30 items, covering 6