来自董剑的问题
【seniorhighschoolEnglish1.什么情况用have什么情况用havebeen?alotoffactories____havebeensetup对havesetup错setup好像是点动词词组吧.怎能用been?2.theirdutyisto__theircountryagainstforeignenemies'sattacks.Adef】
seniorhighschoolEnglish
1.什么情况用have什么情况用havebeen?
alotoffactories____
havebeensetup对havesetup错
setup好像是点动词词组吧.怎能用been?
2.theirdutyisto__theircountryagainstforeignenemies'sattacks.
AdefeatBdefend咋选B
3.Coalwasformedoutofdeadforestsbychemical__.
AprocessesBproduct咋选A
