我來(lái)回答吧!你可要給分啊!
1.there is和there are表示“有”這個(gè)狀態(tài),重在“存在”的意思.前者是接單數(shù)名詞,后者接復(fù)數(shù)名詞.注意：就近原則（就是單復(fù)數(shù)只看離它最近的一個(gè)名詞）.
have和has表示從屬的關(guān)系,意思是誰(shuí)有什么什么.前者是一般式,后者是第三人稱(chēng)單數(shù)形式.
例：There are two apples in her hand.
She has two apples.
2.這個(gè)do是助動(dòng)詞,幫助動(dòng)詞提問(wèn).而be幫助名詞等提問(wèn).
例：Is he doing his homework?
Does he do his homework?
3.情態(tài)動(dòng)詞后所有動(dòng)詞用原型.