1 be good at 表示“善于,在……方面(做得,學得)好”。
He is good at physics. 他物理學得好。
We must be good at learning from others. 我們要善于向他人學習。
2 be good for 意為“對……有益,對……有用”。
Washing hands before meals is good for your health. 飯前洗手對健康有益。
The pill is good for a headache. 這種藥對頭痛有用。
3 be good to 意為“對……好”。
She is good to the old. 她待老人好。
4 be bad for 意為“有害于……”。
Reading in the sun is bad for your eyes. 在太陽底下閱讀對眼睛不利。