A:a>1
B:a<1
C:a≥1
D:a≤1
— Don't ________. Listen to what the teacher is saying carefully.
— Yes, I see.
著名教育家赞可夫指出:“学生在课堂上应过着一种积极的、有血有肉的生活。否则,学生就会终日处于冷漠、惊恐的环境下,他们就不可能正常的发展。”这段话启示我们( )