take sb.aback 表示“使某人吃驚”或“使某人嚇了一跳”.be taken aback 是take sb.aback的被動式,意思是“（某人）處于驚愕狀態(tài)”或“（某人）被嚇了一跳”.
　　take sb.back 表示“使某人回想起過去”；take sth.back 表示“收回所說的話或所寫的東西”,即“把…收回/取消”.be taken back 是take sb./sth.back 的被動式,意思是“某事被收回/取消”或者“某人被帶回到過去”.
　　前者指人,后者指既人也指物.因此,be taken aback 要用人作主語.be taken back 可以用人作主語或也可以用物作主語.例如：
　　I was momentarily taken aback.我一時被嚇呆了.
　　The little girl screamed and we were taken aback.小女孩的尖叫聲嚇了我們一跳.
　　I am taken back by the story.這個故事使我想起了過去.
　　If I buy something and he doesn't like it,I'll have it taken back.要是我買的東西他不喜歡的話,我就會把它退掉.