If I had not stood under the ladder to catch you when you fell, you （ ）now.

A.could not have smiled B.would not be smiling C.did not smile D.will not smile

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 （ ）.

A.methods of cleaning teeth B.methods of caring for teeth C.development of toothpaste D.dental history
问题2：
A.cleaning B.removal C.replacement D.brushing
问题3：
A.also developed the toothbrush B.had more dental problems than other culture C.were the first to support artificial teeth D.did not keep records of their dental practices
问题4：
A.strengthening B.beautifying C.coloring D.extracting
问题5：
A.concentrating on the gums B.getting a foaming effect C.reducing sensitivity D.emulsifying agent.

Universities are institutions that teach a wide variety of subjects at advanced levels. They also carry out research work aimed （1）extending man’s knowledge of these subjects. The emphasis given to each of these functions （2）from university to university, according to the views of the people in （3） and according to the resources available.The smaller and newer universities do not （4）the staff or equipment to carry out the （5） research projects possible in larger institutions. （6） most experts agree that some research activity is （7） to keep the staff and their students in （8） with the latest developments in their subjects.Most students attend a university mainly to （9） the knowledge needed for their chosen （10）. Educationists believe that this aim should not be the （11） one. Universities have always aimed to produce men and women （12） judgment and wisdom as well as knowledge.For this reason, they （13） students to meet others with differing （14）and to read widely to （15） their understanding in many fields of study. （16） a secondary school course, a student should be interested enough in a subject to enjoy gaining knowledge for its own （17） . He should be prepared to （18）every effort to study his chosen （19） in depth. He should have an ambition to make some （20） contribution to man’s knowledge.

A.at B.by C.to D.in
问题2：
A.turns B.range C.moves D.varies
问题3：
A.prospect B.place C.control D.favor
问题4：
A.occupy B.possess C.involve D.spare
问题5：
A.maximum B.medium C.virtual D.vast
问题6：
A.But B.As C.While D.For
问题7：
A.natural B.essential C.functional D.optional
问题8：
A.coordination B.accordance C.touch D.grasp
问题9：
A.acquire B.accept C.endure D.ensure
问题10：
A.procession B.profession C.possession D.preference
问题11：
A.typical B.true C.mere D.only
问题12：
A.with B.under C.on D.through
问题13：
A.prompt B.provoke C.encourage D.anticipate
问题14：
A.histories B.expressions. C.interests D.curiosities
问题15：
A.broaden B.lengthen C.enforce D.specify
问题16：
A.amid B.after C.over D.upon
问题17：
A.object B.course C.effect D.sake
问题18：
A.take B.make C.suffer D.pay
问题19：
A.field B.scope C.target D.goal
问题20：
A.radical B.truthful C.meaningful D.initial

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

A.overextend B.overdraw C.overvalue D.overpay

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

A.conservation B.reservation C.exhaustion D.devastation

In a competitive and fast-paced modern society, busy business executives are so（ ）their work that they hardly know what the word leisure means.

A.engrossed in B.exempt from C.skeptical of D.extraneous to