have been down 和 have down 区别是?

have been down 和 have down 区别是? down 与have been down的区别 have been striking down和have been struck down 第一句有语法错误吗?最好有例句 I have been asked to have the tree cut down.和I have been asked to cut down the tree.有什么区别么? I have been down for two hours.句型转换 I have been down ---- ---- ----. to have been pulled down,不定式的被动完成时态和having been pulled down动名词的被动完成时态,他们有什么不同啊?求讲解 have been doing,had been doing,will have been down是什么 have since been 和 have been since have been 和have ever been区别! Meredith Andrews唱的only to be yours中文歌词Undivided,strip everything else away,Burn the idols,the things in my life that have replaced You,I lay my life down here on Your alter,Empty my hands of all I've been holding backTake everything I hav We should have been so down well的中文翻译是什么 They have been down long as two hours. The work （）down by the time you get hereA：will have been down B：is down C：had been downD：would have down 选什么 为什么啊 I have been down for two hours.改为同义句I have been down ( )( )（ ）two hours. HAV BEEN DOING STH为什么要加BEEN? have been 和 has been的区别 has been和have been区别 In the picture,all the trees have been cut down.句子中为什么加been