Design of all the new tools and implements is based on careful experiments with electronic instruments. First, a human "guinea pig" is tested using a regular tool. Measurements are taken of the amount Of work done, and the buildup of heat in the body. Twisted joints and stretched muscles can not perform as well, it has been found, as joints and muscles in their normal positions. The same person is then tested again, using a tool designed according to the suggestions made by Dr. Tichauer. All these tests have shown the great improvement of the new designs over the old.
One of the electronic instruments used by Dr. Tichauer, the myograph (肌动记器), makes visible through electrical signals the work done by human muscle.
Another machine measures any dangerous features of tools, thus proving information upon which to base a new design. One conclusion of tests made with this machine is that a tripod (三脚架) stepladder is more stable and safer to use than one with four legs.
This work has attracted the attention of efficiency experts and time-and-motion-study engineer, but its value goes far beyond that. Dr. Tichauer’s first thought is for the health of the tool user. With the repeated use of the same tool all day long on production lines and in other jobs, even light manual work can put a heavy stress on one small area of the body. In time, such stress can cause a disabling disease. Furthermore, muscle fatigue is a serious safety hazard.
Efficiency is the by-product of comfort, Dr. Tichauer believes, and his new designs for traditional tools have proved his point.
From the passage we know that joints and muscles perform best when ______ .

A:they are twisted and stretched B:they are in their normal positions C:they are tested with a human "guinea pig" D:they are tested with electronic instruments

Passage Four

From the passage we know that joints and muscles perform best when ______ .

A:they are twisted and stretched B:they are in their normal positions C:they are tested with a human "guinea pig" D:they are tested with electronic instruments

New Technique Promises Earlier Cancer Detection A new technique could revolutionize the early detection of cancer, giving sufferers a greater chance of beating the disease, American scientists said. Researchers at the Massachusetts Institute of Technology have devised a novel method of 【51】 changes in the nucleus of cells in the earliest stages of the disease." More than 85 percent of all cancers originate in the epithelium (上皮) that lines the internal surfaces of organs 【52】 the body. Although these are treatable 【53】 they are diagnosed in one of the preventable stages, early body damages are almost 【54】 to detect," said scientist Feld. " We present a new optical-probe (光学探子) technique based on light-scattering spectroscopy (分光镜检查) that is able 【55】 detect precancerous and early cancerous cells in cell-rich epithelia," he added in a statement. The new technique relies on the fact 【56】 cell nuclei change in the early stages of cancer and the differences scatter light in a characteristic way. Until now the changes were only detectable 【57】 a biopsy (活检) was taken, the scientists said. The new technique, 【58】 in the science journal Nature, can be used in conjunction with a routine cancer screening and surveillance technique which uses an endoscope (内窥镜) —a flexible optical probe 【59】 with cameras which is inserted into a cavity in the body—to check 【60】 cancers. The scientists said they 【61】 their new technique in four different organs during routine endoscopic cancer screening. The tip of the optical probe was brought into contact with the tissue to be tested and the scattering of light was recorded without the need for any tissue to be 【62】 , the scientists said. " Our results show that light-scattering spectroscopy has the potential to detect pre-cancerous body damages and preinvasive cancers throughout the body. This technique should 【63】 improve the efficiency of cancer screening and surveillance," the scientists said. Cancer is one of the biggest 【64】 in industrialized countries. 【65】 to figures from the World Health Organization, 10 million people were diagnosed with the disease worldwide in 1997 and six million died.

A:had to test B:had tested C:have tested D:have been testing

? ?The Centers for Disease Control and Prevention has confirmed cases of swine ?(51) ? in eight students at a New York preparatory (预科的) school, Mayor Michael Bloomberg said Sunday. The students have had only ?(52) ? symptoms and none have been hospitalized, he said. Some of the students have already recovered.
? ?More than 100 students were absent from ?(53) ? due to flu-like symptoms last week. New York health officials tested samples for eight students Saturday and determined the students were probably. ?(54) ? from swine flu, and the CDC confirmed the ?(55) ? on Sunday, Bloomberg said.
? ?The announcement brings the ?(56) ? of confirmed swine flu cases in the United States to 20. Bloomberg said there is no ?(57) ? of a citywide outbreak of the flu, and no sign of a potential outbreak of swine flu at ?(58) ? schools.
? ?Some students at the school ?(59) ? spring break in Mexico, Bloomberg said, but authorities have not determined ?(60) ? any of the students with a confirmed case of swine flu was in Mexico. Someone who traveled to Mexico may not have had any flu symptoms but ?(61) ? on the flu to someone else, he noted.
? ?Bloomberg called on students who are home sick to ?(62) ? home for 48 hours after their symptoms subside.
? ?If symptoms are normal for a regular kind of flu, there is ?(63) ? need to go to a hospital, said Bloomberg. If symptoms become severe, as ?(64) ? any illness, people should go to the hospital, he said.
? ?St. Francis, which has 2,700 students, announced it will remain closed for two days. ?(65) ? whether the students’ illnesses have been minor because they’re young and healthy or because it is a minor strain of the virus, Frieden responded, "We don’t know. /

A:Told B:Tested C:Greeted D:Asked

New Technique Promises Earlier Cancer Detection A new technique could revolutionize the early detection of cancer, giving sufferers a greater chance of beating the disease, American scientists said. Researchers at the Massachusetts Institute of Technology have devised a novel method of 【51】 changes in the nucleus of cells in the earliest stages of the disease." More than 85 percent of all cancers originate in the epithelium (上皮) that lines the internal surfaces of organs 【52】 the body. Although these are treatable 【53】 they are diagnosed in one of the preventable stages, early body damages are almost 【54】 to detect," said scientist Feld. " We present a new optical-probe (光学探子) technique based on light-scattering spectroscopy (分光镜检查) that is able 【55】 detect precancerous and early cancerous cells in cell-rich epithelia," he added in a statement. The new technique relies on the fact 【56】 cell nuclei change in the early stages of cancer and the differences scatter light in a characteristic way. Until now the changes were only detectable 【57】 a biopsy (活检) was taken, the scientists said. The new technique, 【58】 in the science journal Nature, can be used in conjunction with a routine cancer screening and surveillance technique which uses an endoscope (内窥镜) —a flexible optical probe 【59】 with cameras which is inserted into a cavity in the body—to check 【60】 cancers. The scientists said they 【61】 their new technique in four different organs during routine endoscopic cancer screening. The tip of the optical probe was brought into contact with the tissue to be tested and the scattering of light was recorded without the need for any tissue to be 【62】 , the scientists said. " Our results show that light-scattering spectroscopy has the potential to detect pre-cancerous body damages and preinvasive cancers throughout the body. This technique should 【63】 improve the efficiency of cancer screening and surveillance," the scientists said. Cancer is one of the biggest 【64】 in industrialized countries. 【65】 to figures from the World Health Organization, 10 million people were diagnosed with the disease worldwide in 1997 and six million died.

A:had to test B:had tested C:have tested D:have been testing

下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。

A:Told B:Tested C:Greeted D:Asked

New Technique Promises Earlier Cancer Detection A new technique could revolutionize the early detection of cancer, giving sufferers a greater chance of beating the disease, American scientists said. Researchers at the Massachusetts Institute of Technology have devised a novel method of 【51】 changes in the nucleus of cells in the earliest stages of the disease." More than 85 percent of all cancers originate in the epithelium (上皮) that lines the internal surfaces of organs 【52】 the body. Although these are treatable 【53】 they are diagnosed in one of the preventable stages, early body damages are almost 【54】 to detect," said scientist Feld. " We present a new optical-probe (光学探子) technique based on light-scattering spectroscopy (分光镜检查) that is able 【55】 detect precancerous and early cancerous cells in cell-rich epithelia," he added in a statement. The new technique relies on the fact 【56】 cell nuclei change in the early stages of cancer and the differences scatter light in a characteristic way. Until now the changes were only detectable 【57】 a biopsy (活检) was taken, the scientists said. The new technique, 【58】 in the science journal Nature, can be used in conjunction with a routine cancer screening and surveillance technique which uses an endoscope (内窥镜) —a flexible optical probe 【59】 with cameras which is inserted into a cavity in the body—to check 【60】 cancers. The scientists said they 【61】 their new technique in four different organs during routine endoscopic cancer screening. The tip of the optical probe was brought into contact with the tissue to be tested and the scattering of light was recorded without the need for any tissue to be 【62】 , the scientists said. " Our results show that light-scattering spectroscopy has the potential to detect pre-cancerous body damages and preinvasive cancers throughout the body. This technique should 【63】 improve the efficiency of cancer screening and surveillance," the scientists said. Cancer is one of the biggest 【64】 in industrialized countries. 【65】 to figures from the World Health Organization, 10 million people were diagnosed with the disease worldwide in 1997 and six million died.

A:had to test B:had tested C:have tested D:have been testing