教师的专业素养包括先进的教育理念、良好的教育能力和一定的______。
参考答案：研究能力
Two or three years ago this kind of glasses _______ a favorite for some time, but now it _______.
A．were, has gone over
B．was, has gone out
C．was, has gone away
D．were, is going down
简述集体合同的形式。
