teenagers are （）（）exercise every day to（）（） 为了保持健康,青少年应该天天锻炼身体

teenagers can't drive cars because they are't （c ） enough. Teenagers are not ______（应该）to smoke because smoking is bad for their health. teenagers are （）（）exercise every day to（）（） 为了保持健康,青少年应该天天锻炼身体 EXW（EX works）中的EX是指什么?export? The famous writer （）（write）two books so far which are popular with teenagers 动词填空 有点难!）We are teenagers,we have pocket money every week,Do you know how we spend () pocket money? teenagers 选出错误的一项并改正 （）1.（①Teenagers ）are always （②exciting）（③about）（④playing football）改正:（ ） -----i do not think teenagers should drive cars,---（i agree）,they are not serious enough.怎么翻译,有无固定用法,或回答 . many ads are aimed------(special) at teenagers. most teenagers are i_______in chatting on line 高等数学求导 y=﹙1+ex）/（1-ex）求y=（1+ex）/（1-ex）导数 不定积分∫（2x+ex）dx 求 小小克星EX（Little Busters!EX）求 小小克星EX的下载（Little Busters!EX）或直接发在百度知道里 （18）Some ads are aimed ____at teenagers so that some young people（18）Some ads are aimed ____at teenagers so that some young people see many advertisements a day.A specially B especially C unusually D greatly（20）I know he hasn't finished t 设随机变量X满足EX的平方等于16,DX=4,则EX=（ ） 麻烦列举一下前缀为ex表“以前的”的英语单词（如ex-girlfrieng）,越多越好, f (x )=ex+1/ex,证明f(x)在（0,+00）上是增函数