据估计，目前全世界动物有150多万种，植物有50多万种。这说明（   ）

下列性质中，矩形不一定具有的是(    )

下列说法正确的是（　　）

①人具有体温恒定、胎生、哺乳等特征   

②与人亲缘关系最近的是类人猿

③人类的原始祖先是森林古猿           

④由古猿进化成人类经过了极其漫长的岁月．

    A good book can be satisfying, can improve your knowledge and can teach you a lot. There are several ways to develop a lifetime reading habit.

    Set times. You should have a few set times every day when you'll read for at least 5—10 minutes, no matter what happens. For example, make it a habit to read during breakfast and lunch (and even dinner if you eat alone).

    Always carry a book. No matter where you go, take a book with you. When you leave the house, make sure to have at least one book. You may keep the book in the car, or into the office or to anywhere you go, unless you' re sure you won't have time to read.

    Make a list. Keep a list of all the great books you want to read. You can keep this in a pocket notebook. Be sure to add to it whenever you hear about a good book. Keep a running list, and cross out the ones you have read.

    Find a quiet place. Find a place in your home where you can sit in a comfortable chair without television or computer near the chair. There should be no music or noisy family members.

    Set a high aim. For example. Tell yourself that you want to read 50 books this year. Your best to finish reading them. Just be sure you're still enjoying the reading.

中国农村问题研究中心主任徐勇说，农村改革的这30年，分成三个阶段。第一个阶段：1978—1988年的黄金十年……第二阶段1988—2002年的曲折十五年……第三阶段：2003—2007年的历史跨越五年……三个阶段都有一些相应的关键词，对应正确的一组是