【改错】Before you came to teach us English at last term.这句话为什么要去掉at?

they came before three hours.改错 he came here two hours before 改错 【改错】Before you came to teach us English at last term.这句话为什么要去掉at? Where_____you______(study)before you came here? what did do before you came to China 中文翻译 Turn the light off before you go home,please.改错 What did happen to you the day before yesterday?(改错) 改错题 you must are home before ten o'clock. 改错.Knock before you enter into the room. You came the day before yesterday." before " 是什么词 came before the house 改错The tyohoon washed over two thousands of hens away.He said lightning always came before thunder. how much english did you know before you came to our school 回答none 还是 nothing? Where were you before you came here?I___(stay) in the UK for half a year Where were you before you came here?I___(stay) in the UK for half a year. you came me after so long before I have been waiting for you是什么意思? 改错!Do you make a list for the things you want to buy before going shopping? You should stop having a look before you cross the street.(改错）