新中国成立后，中国人民从此过上了幸福安宁的生活。为什么在第一届中国人民政治协商会议上还要将曾经激发中华民族英勇战斗的《义勇军进行曲》定为国歌呢？为什么还要时时唱起“中华民族到了最危险的时候”呢？用一个成语来表达是（    ）

下列属于许诺时应考虑的因素有（  ）

①自己的实际能力            ②对方的胃口有多大

③有无实现的可能性        ④是否符合法律和道德的要求

1923年丹麦化学家布朗斯特提出一种理论叫酸碱质子论，人为规定凡是能够释放质子(H⁺)的任何物质（包括分子或离子）都是酸，任何能接受质子的分子或离子都是碱，根据这一理论，下列各项既属于酸又属于碱的是（ ）

将△ABC绕点B逆时针旋转α得到△DBE，DE的延长线与AC相交于点F，连接DA、BF．

（1）如图1，若∠ABC=α=60°，BF=AF．

①求证：DA∥BC；②猜想线段DF、AF的数量关系，并证明你的猜想；

（2）如图2，若∠ABC＜α，BF=mAF（m为常数），求$\frac{DF}{AF}$的值（用含m、α的式子表示）．

完形填空
    Could we look back some day and say that Warren Buffett's greatest genius(天才) was finding two talented people to replace(代替)him? These two people are Ted Weschler, aged 56，and Todd Combs，aged 46，who have been chosen by Buffett as money managers to begin to1 the key investment(投资)operations of Berkshire Hathaway.
    But how did Ted and Todd catch Buffett's2? "These are the only two persons I could find, who read as 3 as I did, " Buffett says with a laugh. Actually he's not really kidding. Both Ted and Todd spend lots of time 4.
    Ted spends half a day reading many materials like5and trade periodicals(期刊). In a recent interview，Ted 6 that to become a successful investor, one needs to be hungry, curious and read all the time. Different kinds of reading will allow you to 7things that might give you an insight(洞察力)to where a business is going in five years.
    And Todd describes himself as a book with legs. He gets up at around 7 or 8 a.m. and reads 8about 7 or 8 p.m. . After dinner; he also leads for 9 hour or two in bed.
    What's the secret for financial success? It seems that 10a habit of reading really matters.