You should be more respectful when talking to teachers.
Cantonese
恭敬不如从命
恭敬不如從命
I'd better obey you rather than keep being too polite.
Examples (Wiktionary)
Mandarin
我们必须向一切内行的人们(不管什么人)学经济工作。拜他们做老师,恭恭敬敬地学,老老实实地学。
我們必須向一切內行的人們(不管什麼人)學經濟工作。拜他們做老師,恭恭敬敬地學,老老實實地學。
wǒ men bì xū xiàng yī qiè nèi xíng de rén men ( bù guǎn shén me rén ) xué jīng jì gōng zuò . bài tā men zuò lǎo shī , gōng gōng jìng jìng de xué , lǎo lǎo shí shí de xué .
We must learn to do economic work from all who know how, no matter who they are. We must esteem them as teachers, learning from them respectfully and conscientiously.