听老师的话，要听全哦。ill不做限定用法的形容词，是指“生病的”。但如果当做限定形容词来用，意思是“坏的”、“不好的”，与生病与否无关。

所以ill mother，在这里是“坏的”、“歹毒的”之类的意思，与疾病无关。

   《薄冰英语惯用法词典》指出：“ill (有病的）在现代英语中（特别是美国英语中），作定语的用法已日益普遍。例如：A hospital is a place where ill people stay and have treatment which should cure them. 医院是病人在那里接受治疗的地方。/ But like many ill men, they resented the well. 然而像许多病人一样，他们憎恨健康的人。/ The nurses were taking care of those wounded and ill soldiers. 护士门正在护理伤病员。”

    其它一些用 ill (有病的）作定语的例句：The ill people ...(Reading Faster)病人 ...... / ... in order to spend more time with his seriously ill wife ... (TIME)......为了跟重病的妻子多度过一些时光 ......（摘自赵振才：《英语常见问题解答大词典》增订版第四版）

ill 用法1只能作表语，用法2可以作定语

A:ill 有病的;不健康的  只能作表语。

B:ill 作定语，表示 有害的。

(1)ill adj.有病的;不健康的 (英语解释：Someone who is ill is suffering from a disease or a health problem.)

In November 1941 Payne was seriously ill with pneumonia. 

1941 年 11 月,佩恩得了严重的肺炎。

I was feeling ill. 

我觉得自己生病了。

(2)有害的;讨厌的 （英语解释You can use ill in front of some nouns to indicate that you are referring to something harmful or unpleasant.）

She had brought ill luck into her family.  

她给家庭带来了厄运。

He says that he bears no ill feelings towards Johnson.  

他说他对约翰逊并无恶感。