我国地势呈阶梯状分布，关于其地理意义，下列叙述正确的是[ ] A．地势落差大，水 发布时间：2017-06-15 18:40 │ 来源：www.tikuol.com 题型：双选题 问题： 我国地势呈阶梯状分布，关于其地理意义，下列叙述正确的是[ ]A．地势落差大，水利资源丰富B．使我国许多大河由西向东流C．不利于海洋湿润气流深入内陆D．使沿海和内地的经济联系受到限制
题型：双选题 完形填空。Dear Li Fei, Hi! I'm Jim. _ 16 _ to meet you. It's very exciting to have a Chinese friend ! In America, schools _ 17 at eight- thirty, so I get up _ 18 _ seven o'clock. What 19 do schools start in China? In our school, we have a lot of subjects. My favorite subject is history, 20 I think it's interesting and I really like my 21 Mr. Hall. What's your favorite subject? My last class is at four o'clock, and 22 school I like to play basketball. Can you play basketball? I can play 23 violin but I can't play 24 very well. What are your hobbies? Please tell me about 25 life in China. Best wishes,( )1. A. Good ( )2. A. starts ( )3. A. at ( )4. A. time ( )5. A. because ( )6. A. teachers ( )7. A. when ( )8. A. a ( )9. A. them ( )10. A. your B. Luck B. is B. on B. class B. for B. studentB. over B. an B. it B. you C. Nice C. are C. in C. date C. but C. teacher C. after C. the C. one C. my D. Kind D. start D. of D. day D. so D. friend D. before D. / D. violin D. her 查看答案
题型：双选题 取5 mL 0.1 mol·L-1KI溶液，滴加0.1 mol·L-1FeCl3溶液5～6滴，继续加入2 mLCCl4，充分振荡，静置。下列有关该实验的说法不正确的是A．下层CCl4溶液呈紫红色B．取少量上层溶液，滴加酸性AgNO3溶液，若有黄色沉淀产生，则表明该反应存在化学反应限度C．取少量上层溶液，滴加KSCN溶液，若溶液显红色，则表明该反应存在化学反应限度D．该实验中KI与FeCl3反应后（未加CCl4），溶液中存在Fe3+、Fe2+、I—、I2等微粒 查看答案
题型：双选题 下列叙述中错误的是( )。A) 在数据库系统中，数据的物理结构必须与逻辑结构一致B) 数据库技术的根本目标是要解决数据的共享问题C) 数据库设计是指在已有数据库管理系统的基础上建立数据库D) 数据库系统需要操作系统的支持 查看答案