My request for a day off（ ） by the manager of the company.

A.was turned off B.was turned down C.was put down D.was put away

The development of toothpaste began as long ago as 3000/5000BC in the ancient counties of China and 304. According to Chinese history, Huang-Ti claimed different types of pair felt in the mouth could be cured by sticking gold and silver needles into different parts of the jaw and gum. It was theories such as these that led to the development of dental cream. During the years 3000/5000BC, Egyptians made toothpaste using a recipe of powdered ashes of hooves of oxen, myrrh, powdered and burned egg shells and pumice. It is assumed that the ancient Egyptians used their fingers to rub the mixture onto teeth.The too shtick, the forerunner of the toothbrush had not, as far as is known, been discovered at this time. From the records of the ancient countries of India China and Egypt, it was the Greeks and Romans who developed and improved toothpaste and developed a leaden instrument for the extraction of teeth. They were also the first to bind loose teeth together and to support artificial teeth by means of gold wire. During 1000AD, the Persians, gave advice on the dangers of using hard toothpowder and recommendations were made to make toothpowder from burnt hart-shorn, the burnt shells of snails and oysters and burned gypsum.Other Persian recipes included dried animal parts, herbs, honey and minerals. One formula for strengthening teeth included green lead, verdigris, incense, honey and powdered flint-stone.Toothpowder or dentifrice, was first available in Britain in the late 18th century. It came in a ceramic pot and was available either as a powder or paste. The rich applied it with brushes and the poor with their fingers. The powders were developed by doctors, dentists and chemists and often contained ingredients that were highly abrasive and harmful to the teeth, such as brick dust, china, earthenware or cuttlefish, and to make them more palatable, they contained glycerin. By the early nineteenth century, the ingredient strontium was introduced, to strengthen teeth and reduce sensitivity, but it only really concentrated on the gums. In the late 18 century, borax was introduced in the U.S. and in, 1896, Dental Cream was first packaged in powder was used to get the foaming effect. In 1873, an aromatic toothpaste in a jar: collapsible tubes. Before the Second World War, the majority of toothpaste on the market used soap as an emulsifying agent, even though it was known that soap had certain inherent defects.1.What is the main subject of the passage?2.The word "extraction" in line 11 refers to （ ）.3.According to the passage, it can be inferred that the Greeks and Romans （ ）.4.The author mentions that the Persians used toothpowders for which purpose other than cleaning teeth?5.According to the passage, strontium was most useful for （ ）.

He always included something above the understanding of his hearers in order to prevent them from becoming（ ）and to stimulate their desire to learn more.

Consumers may also be permitted to （ ）their current accounts for a short period in the anticipation of a credit item coming in.

The history helps explain the vexing dispute between the European Union and the United States over the greatest threat to privacy yet conceived: the hundreds of millions of personal dossiers in computerized and networked da¬tabases.

To achieve sustainable development, the （ ）of resources is assuming new importance.