优秀的培训师在培训中应该扮演好的角色包括（）。
A.教师
B.教练
C.咨询顾问
D.演员
参考答案：A, B, C, D
Shirley _____ a book about China last year but I don't know whether she has finished it. [ ]
A. has written
B. wrote
C. had written
D. was writing
历史教材对学生学习历史的影响。
