Why are you tired? Because I walked a long way.分析：tired是形容词,在句子中作表语,所以可用系动词be来做谓语.当然还可以是： Why do you feel tired? (feel同样是系动词,但其法定式、疑问式需要用助动词do形成） Because I walked a long way.
怎么样分清WHY 后加助动词还是BE动词?
Why are you tired? Because I walked a long way.分析：tired是形容词,在句子中作表语,所以可用系动词be来做谓语.当然还可以是： Why do you feel tired? (feel同样是系动词,但其法定式、疑问式需要用助动词do形成） Because I walked a long way.