Laziness is a sin(罪), everyone knows that. We have probably all had lectures pointing out that laziness is immoral, that it is wasteful, and that lazy people will never amount to anything in life. B
During the nineteenth and twentieth centuries, migrations have taken place within 11 countries; the cities with their industries have attracted people away from the country. The possibility of earning
Plastics are materials which are softened by heat and set into lasting form when shaped in a mold. Some are natural; some are semi-synthetic(半合成的) , the result of chemical action on natural su
In today's world, insurance plays a vital role in the economic and social welfare of the entire population. The wish to guard against dangers to life and property is basic to human nature. By using va
The difference between a liquid and a gas is obvious under the conditions of temperature and pressure commonly found at the surface of the Earth. A liquid can be kept in an open container and fill it
Homing pigeons are placed in a training program from about the time they are twenty-eight days of age. They are taught to enter the cage through a trap and to exercise above and around the loft(鸽棚
Are some people born clever, and others born stupid? Or is intelligence developed by our environment and our experiences? Strangely enough, the answer to both these questions is yes. To some extent ou
Scientists at Sussex University appear to be on the way to 11 how the mosquito, carrier of diseases such as malaria and yellow fever, homes in on its target. The problem is that they have found that t
In the United States, it is not 11 to telephone someone very early in the morning. If you telephone him early in the day, while he is shaving or having breakfast, the time of the call shows that the m
At the close of each business day, most trained teachers, administrators, politicians, and statesmen make objective analyses of all that has transpired. They then carefully evaluate performance in the