句中有謂語(yǔ)動(dòng)詞的話就要用DO DOES,作為助動(dòng)詞；句中賓語(yǔ)是形容詞或名詞的話就要is are,作為系動(dòng)詞.當(dāng)句子主語(yǔ)是第三人稱時(shí),助動(dòng)詞(do)就要用三單形式does,系動(dòng)詞(is,are)就要用is.另外,當(dāng)句中主語(yǔ)是單數(shù)的話,系動(dòng)詞也要用is.
如Is he a boy?he是三單,所以用is
Are they boys?they 是復(fù)數(shù),所以用are
Does he eat meat?eat是謂語(yǔ)動(dòng)詞,所以要用助動(dòng)詞do,因?yàn)閔e 是三單,所以用does
Do they eat meat?eat是謂語(yǔ)動(dòng)詞,所以用助動(dòng)詞do,因?yàn)閠hey 是復(fù)數(shù),所以就不用does,仍舊用docan must will have呢？