①近代史上第一次取得完全胜利的民族解放战争

②洗雪了近代以来的民族耻辱，增强了民族自信心

③成为中华民族由衰败到重新振兴的转折点

④标志着新民主主义革命的胜利，中国人民从此站起来了

Tom and Steve were twin brothers. Tom loved to play basketball. But Steve loved to read books. One day Tom was playing basketball    21  he fell and broke his leg. When they took him to the hospital, the doctor said he wouldn’t be able to play for six months. Steve went    22  him to and brought him books on basketball. At first Tom wasn’t going to read them. Then he began to read them and 23 that there were ways he could play basketball better. He began to think that books weren’t    24  .

    When Tom’s leg started getting better, Steve would help him by going for walks with him.  25 Tom’s doctor said he could start playing basketball again. Then Tom showed Steve how to toss(投)for baskets. Steve found that he enjoyed it.

    Then Tom was ready to   26   the basketball games. Steve went to watch the games and enjoyed himself. They then    27   practiced basketball and read books together.

    So you can see, when    28    happens, something good may also happen. Steve showed Tom about books and Tom showed Steve about basketball.

So you can also   29   showing others something that you like to do and they can show you something that they like to do. 30 you can find new things to do.

21A. until              B. when            C. after           D. where

22A. on seeing          B. to call            C. to visit         D.to look

23A. saw              B. looked            C. read           D. found

24A. good             B. bad              C. better           D. worse

25A. But              B. However          C. Finally         D. So

26A. take              B. win              C. lose            D. join in

27A. always            B. never            C. seldom          D. much

28A. anything good      B. something nice     C. something bad   D. anything wrong

29A. try               B. practice           C. enjoy          D. like

30A . On the way       B. By the way        C. In a way       D. In this way

如图所示的是某池塘中的浮萍蔓延的面积$\left(m^2\right)$与时间x（月）的关系：$y=a^x$，有以下叙述：① 这个指数函数的底数是2；②第5个月的浮萍的面积就会超过30$m^2$；③浮萍从$4m^2$蔓延到$12m^2$需要经过1.5个月；④浮萍每个月增加的面积都相等；⑤若浮萍蔓延到$2m^2$、$3m^2$、$6m^2$所经过的时间分别为$x_1,x_2,x_3$，则$x_1+x_2=x_3$其中正确的是(   )