在英语的句型中一般在什么情况下用到is are am...又一般在什么情况下用到do does

Is he a student?
Am I beautiful?
Are they ten years old?
这些主系表结构的句子中需要be动词
Do they like playing basketball?
Does he look like his father?
这些后面是动词,诸如play 、look,他们做一般疑问句的时候需要借助助动词do或者does