Although substantial progress had been made, sulfur dioxide and monoxide levels were up 25 percent nationally and particulates were increased by more than 14 percent. What is more, pollution levels in a dozen cities were higher than those of 1970. Of 20,000 major stationary sources of air pollution, about 5,000 failed to meet the schedules, and well over half the steel plants and nonferrous smelters in the United States continued to be in violation of federal regulations.
On April 26, 1986, another serious incident alarmed the world. One of four nuclear reactors at Chernobyl, about 130 km (about 80 mi) north of Kyiv (now in Ukraine) in the USSR, exploded and burned. Radioactive material spread over Scandinavia and northern Europe, as discovered by Swedish observers on April 28. According to the official report issued in August, the accident was caused by unauthorized testing of the reactor by its operators. Radiation about 50 times higher than that at Three Mile Island exposed people nearest the reactor, and a cloud of radioactive fallout spread westward. Unlike most reactors in western countries, including the United States, the reactor at Chernobyl did not have a containment building. Such a structure could have prevented material from leaving the reactor site.
动物保护(关键词：bald eagles, wildcats, buffalos)
More animals have been found on the verge of extinction. Recently, the Federal Government has put wild cats, bald eagles on the list. And buffalos had almost been erased from the American continent.
沉迷网络(关键词：boost self-confidence增强自信, take refuge：逃避现实，stress:压力，withdraw: 离群
According to psychologists, many young people suffering from shyness also risk becoming addicted to computers. Success with computers provides them with the self-confidence they lack in their personal lives. Zimbardo fears that shy youngsters who take refuge in the computer may fail to learn and practice important social skills needed later in life.
盗版产品(safeguard intellectual property，CD, videos, CD-ROMs, counterfeit trademarks)
In March, China and the United States averted a trade war when they reached an agreement to safeguard U.S. intell