The Internet affords anonymity to its users, a blessing to privacy and freedom of speech. But that very anonymity is also behind the explosion of cyber-crime that has【C1】________across the Web.

Can privacy be preserved【C2】_____bringing safety and security to a world that seems increasingly【C3】_____?

Last month, Howard Schmidt, the nation’s cyber-czar, offered the federal government a【C4】_____to make the Web a safer place—a “voluntary trusted identity” system that would be the high-tech【C5】__of a physical key, a fingerprint and a photo ID card, all rolled【C6】__one. The system might use a smart identity card, or a digital credential【C7】_____to a specific computer, and would authenticate users at a range of online services.

The idea is to【C8】_____a federation of private online identity systems. Users could【C9】__which system to join, and only registered users whose identities have been authenticated could navigate those systems. The approach contrasts with one that would require an Internet driver’s license【C10】_____ by the government.

Google and Microsoft are among companies that already have these “single sign-on” systems that make it possible for users to【C11】________just once but use many different services.

【C12】_____, the approach would create a “walled garden” in cyberspace, with safe “neighborhoods” and bright “streetlights” to establish a sense of a【C13】_____community.

Mr. Schmidt described it as a “voluntary ecosystem” in which “individuals and organizations can complete online transactions with【C14】_____, trusting the identities of each other and the identities of the infrastructure【C15】_____which the transaction runs”.

Still, the administration’s plan has【C16】_____privacy rights activists. Some applaud the approach; others are concerned. It seems clear that such a scheme is an initiative push toward what would【C17】_____be a compulsory Internet “driver’s license” mentality.

The plan has also been greeted with【C18】_____by some computer security experts, who worry that the “voluntary ecosystem” envisioned by Mr. Schmidt would still leave much of the Internet【C19】__. They argue that all Internet users should be【C20】_____to register and identify themselves, in the same way that drivers must be licensed to drive on public roads.

The outbreak of swine flu that was first detected in Mexico was declared a global epidemic on June 11, 2009. It is the first worldwide epidemic【C1】________by the World Health Organization in 41 years.

The heightened alert【C2】_____an emergency meeting with flu experts in Geneva that convened after a sharp rise in cases in Australia, and rising【C3】_____in Britain, Japan, Chile and elsewhere.

But the epidemic is “【C4】_____” in severity, according to Margaret Chan, the organization’s director general,【C5】__the overwhelming majority of patients experiencing only mild symptoms and a full recovery, often in the【C6】_____of any medical treatment.

The outbreak came to global【C7】_____in late April 2009, when Mexican authorities noticed an unusually large number of hospitalizations and deaths【C8】__healthy adults. As much of Mexico City shut down at the height of a panic, cases began to【C9】_____in New York City, the southwestern United States and around the world.

In the United States, new cases seemed to fade【C10】_____warmer weather arrived. But in late September 2009, officials reported there was【C11】__flu activity in almost every state and that virtually all the【C12】__tested are the new swine flu, also known as (A) H1N1, not seasonal flu. In the U.S., it has【C13】_____more than one million people, and caused more than 600 deaths and more than 6,000 hospitalizations.

Federal health officials【C14】_____Tamiflu for children from the national stockpile and began【C15】_____ orders from the states for the new swine flu vaccine. The new vaccine, which is different from the annual flu vaccine, is【C16】_____ahead of expectations. More than three million doses were to be made available in early October 2009, though most of those【C17】__doses were of the FluMist nasal spray type, which is not【C18】__for pregnant women, people over 50 or those with breathing difficulties, heart disease or several other【C19】__. But it was still possible to vaccinate people in other high-risk groups: health care workers, people【C20】_____infants and healthy young people.