培养学习兴趣是（）学校咨询的重点
A.大学生
B.小学一、二年级学生
C.中学生
D.小学三年级以上学生
参考答案：B
13. ___ had they reached the 30th floor ____ they realized that they had forgotten to take the key.
A．Hardly; than
B．Hardly; when
C．No sooner; when
D．No sooner; then
脑可塑性的主要机制？
