驾驶员要坚持“六不”，（不开冷车、不要熄火、不加空油、不加急速、不能拖档、不用急刹）原则指导节油驾驶。
参考答案：对
She didn’t know__________she could express her ideas clearly when she was invited to speak at the meeting.
A．what
B．why
C．how
D．whether
教师确定的职业发展目标越高越好。（）
