__________the uncertainty about its medical basis, acupuncture has become a popular form of treatment. As ________unique contribution of traditional Chinese medicine, acupuncture spread__________ many other Asian countries, such as Japan, as early as the 6th century. It was introduced__________ the West around the 16th century. In 2010, acupuncture was __________(include)in the UNESCO Intangible Cultural Heritage List. Today, acupuncture is __________(recognize) as a symbol of traditional Chinese culture and has come into widespread use around the world. The World Health Organization recommends acupuncture __________a good treatment for over 100 medical problems. __________ doubts about its safety have gradually disappeared, interest continues to grow.

How acupuncture actually works is not clearly understood. For example, there are different theories __________(try) to explain how it eases pain, but no agreement has been reached. One theory explaining this phenomenon suggests that acupuncture blocks pain signals __________ reaching the brain. Another theory relates acupuncture __________ the production of a substance in the body __________ can reduce pain.

①Over the years, acupuncture __________ (use)to treat a wide variety of health problems, __________ (include) severe pains, blood pressure issues, stomach discomfort, sports injuries and weight problems. And it has been used to treat more than just physical problems——acupuncturists have discovered that the treatment helps with mental problems like depression and anxiety too. Acupuncture has also been applied __________ treat people who abuse alcohol, tobacco or drugs.

According to the results of the check-up, the acupuncturist then selects certain points on the body called acupuncture points. Needles are pushed into the skin at these points __________ that a health problem can be treated. ①Up to now, more than 360 acupuncture points __________(identity), each linked to a different part of the body. Sometimes the needles are pushed into points near the body part affected by a disease, and sometimes into points that are not so close to it.

So what happens during a visit to the acupuncture clinic? First the acupuncturist examines the patient, __________ (look) at the patient’s skin and tongue, __________ (listen) to the sound of his or her voice and breathing, and __________ (smell) his or her breath. Then the acupuncturist asks some questions about the patient’s condition and feels his or her pulse. This is a particularly important step according __________ the energy theory behind acupuncture. The acupuncturist can check the pulse in three positions on each wrist, and every one of them is connected __________ a major body organ. By checking all the positions, the acupuncturist can find out __________ energy channel does not have enough energy.

__________acupuncture developed, the simple bian stones were replaced by stone needles. Eventually, metal needles began to appear and took the place of stone needles. These solid needles are made of different metals, such as gold and silver. Some acupuncturists today still use gold and silver needles, but the majority have now switched __________ stainless steel ones. In addition __________the changes in material the shapes of the needles have also changed over time. __________(origin), there were nine different kinds of needles, with __________(vary) in shape. ①Nowadays, the fine sharp needles that measure usually between 15 and 75 millimetres in __________(long) are still used, while most of the others have been replaced by more complex medical instruments.